c++ basic_strings

通用字符串类该basic_string的是String类的任何字符类型（见字符串描述）的泛化。模板参数图表字符类型。该字符串是通过这种类型的字符序列形成的。这应是一个非数组POD类型。性状性格特征类定义了basic_string的对象（见char_traits）用字的基本属性。特点:: char_type应是一样的图表。别名为成员类型的basic_string::的traits_type。ALLOC分配器对象类型用来定义存储分配模式。默认情况下，分配器类模板时，它定义了简单的内存分配模式，是价值无关。别名为成员类型的basic_string:: allocator_type。注：因为第一个模板参数是不是别名为任何成员类型，图用于整个引用来引用此类型。ms-help://MS.MSDNQTR.v90.chs/dv_vcstdlib/html/1fd8acee-24cb-4e63-946b-de46f868624e.htmhttp://www.cplusplus.com/reference/string/basic_string/?kw=basic_string

#include <string>#include <iostream>//构造函数void basic_stringConstructor(void);//增加了字符的字符串的末尾void basic_string_append(void);//分配新的字符值到字符串的内容void basic_string_assign(void);//在返回字符串中指定位置的参考元素void basic_string_at(void);//返回一个迭代解决的第一个元素在字符串中void basic_string_begin(void);//字符串作为C风格的内容转换，空值终止，串void basic_string_c_str(void);//返回可存储在一个字符串元素的最大数量不增加串的存储器分配void basic_string_capacity(void);//删除字符串中的所有元素void basic_string_clear(void);//进行比较以指定字符串的字符串，以确定该两个字符串相等或者如果一个字典顺序小于另一个void basic_string_compare(void);//副本在从源字符串到目标字符数组索引位置最指定数目的字符void basic_string_copy(void);//副本在从源字符串到目标字符数组索引位置最指定数目的字符void basic_string__Copy_s(void);//字符串的内容转换为字符数组void basic_string_data(void);//测试该字符串是否是包含的字符或没有void basic_string_empty(void);//返回地址字符串中的成功的最后一个元素的位置的迭代器void basic_string_end(void);//删除从指定位置的元素或一个范围中的字符串的元素的void basic_string_erase(void);//搜索在前进方向的字符串为一个字符串的第一个出现的字符的指定序列相匹配void basic_string_find(void);//通过搜索的第一个字符的字符串不是指定字符串的任何元素void basic_string_find_first_not_of(void);//通过搜索的第一个字符的字符串指定字符串的任何元素相匹配void basic_string_find_first_of(void);//通过搜索的最后一个字符的字符串不是指定字符串的任何元素void basic_string_find_last_not_of(void);//通过搜索的最后一个字符字符串，是一个指定字符串的元素void basic_string_find_last_of(void);//返回分配器对象的副本，用于构造串void basic_string_get_allocator(void);//在插入指定位置的元素或多个元素或者一个范围元素融入串void basic_string_insert(void);//返回字符串中的元素的当前数目void basic_string_length(void);//返回一个字符串应该包含字符的最大数量void basic_string_max_size(void);//将一个元素添加到字符串的末尾void basic_string_push_back(void);//返回一个迭代器的第一个元素的字符串逆转void basic_string_rbegin(void);//返回一个指向刚刚超越了逆转字符串中的最后一个元素的迭代void basic_string_rend(void);//在一个字符串替换元素的指定位置与来自其它范围或字符串或C字符串复制指定的字符或字符void basic_string_replace(void);//设置字符串与数的能力至少一样大指定数目void basic_string_reserve(void);//指定一个新的大小为一个字符串，添加或删除元素的要求void basic_string_resize(void);//搜索在向后方向的字符串的子字符串的第一次出现的字符的指定序列相匹配void basic_string_rfind(void);//返回字符串中的元素的当前数目void basic_string_size(void);//副本最多某些字符数的一个字符串的子字符串从指定的位置开始void basic_string_substr(void);//交换两个字符串的内容void basic_string_swap(void);int main(){//basic_stringConstructor();//basic_string_append();//basic_string_assign();//basic_string_at();//basic_string_begin();//basic_string_c_str();//basic_string_capacity();//basic_string_clear();//basic_string_compare();//basic_string_copy();//basic_string__Copy_s();//basic_string_data();//basic_string_empty();//basic_string_end();//basic_string_erase();//basic_string_find();//basic_string_find_first_not_of();//basic_string_find_first_of();//basic_string_find_last_not_of();//basic_string_find_last_of();//basic_string_get_allocator();//basic_string_insert();//basic_string_length();//basic_string_max_size();//basic_string_push_back();//basic_string_rbegin();//basic_string_rend();//basic_string_replace();//basic_string_reserve();//basic_string_resize();//basic_string_rfind();//basic_string_size();//basic_string_substr();basic_string_swap();return 0;}//构造函数void basic_stringConstructor(void){using namespace std;// The first member function initializing with a C-stringconst char *cstr1a = "Hello Out There.";basic_string <char> str1a(cstr1a, 5);cout << "The string initialized by C-string cstr1a is: "<< str1a << "." << endl;// The second member function initializing with a stringstring  str2a("How Do You Do?");basic_string <char> str2b(str2a, 7, 7);cout << "The string initialized by part of the string cstr2a is: "<< str2b << "." << endl;// The third member function initializing a string// with a number of characters of a specific valuebasic_string <char> str3a(5, '9');cout << "The string initialized by five number 9s is: "<< str3a << endl;// The fourth member function creates an empty string// and string with a specified allocatorbasic_string <char> str4a;string str4b;basic_string <char> str4c(str4b.get_allocator());if (str4c.empty())cout << "The string str4c is empty." << endl;elsecout << "The string str4c is not empty." << endl;// The fifth member function initializes a string from// another range of charactersstring str5a("Hello World");basic_string <char> str5b(str5a.begin() + 5, str5a.end());cout << "The string initialized by another range is: "<< str5b << "." << endl;return;/*The string initialized by C-string cstr1a is: Hello.The string initialized by part of the string cstr2a is: You Do?.The string initialized by five number 9s is: 99999The string str4c is empty.The string initialized by another range is:  World.请按任意键继续. . .*/}//增加了字符的字符串的末尾void basic_string_append(void){using namespace std;// The first member function// appending a C-string to a stringstring str1a("Hello ");cout << "The original string str1 is: " << str1a << endl;const char *cstr1a = "Out There ";cout << "The C-string cstr1a is: " << cstr1a << endl;str1a.append(cstr1a);cout << "Appending the C-string cstr1a to string str1 gives: "<< str1a << "." << endl << endl;// The second member function// appending part of a C-string to a stringstring str1b("Hello ");cout << "The string str1b is: " << str1b << endl;const char *cstr1b = "Out There ";cout << "The C-string cstr1b is: " << cstr1b << endl;str1b.append(cstr1b, 3);cout << "Appending the 1st part of the C-string cstr1b "<< "to string str1 gives: " << str1b << "."<< endl << endl;// The third member function// appending part of one string to anotherstring str1c("Hello "), str2c("Wide World ");cout << "The string str2c is: " << str2c << endl;str1c.append(str2c, 5, 5);cout << "The appended string str1 is: "<< str1c << "." << endl << endl;// The fourth member function// appending one string to another in two ways,// comparing append and operator [ ]string str1d("Hello "), str2d("Wide "), str3d("World ");cout << "The  string str2d is: " << str2d << endl;str1d.append(str2d);cout << "The appended string str1d is: "<< str1d << "." << endl;str1d += str3d;cout << "The doubly appended strig str1 is: "<< str1d << "." << endl << endl;// The fifth member function// appending characters to a stringstring str1e("Hello ");str1e.append(4, '!');cout << "The string str1 appended with exclamations is: "<< str1e << endl << endl;// The sixth member function// appending a range of one string to anotherstring str1f("Hello "), str2f("Wide World ");cout << "The string str2f is: " << str2f << endl;str1f.append(str2f.begin() + 5, str2f.end() - 1);cout << "The appended string str1 is: "<< str1f << "." << endl << endl;return;/*The original string str1 is: HelloThe C-string cstr1a is: Out ThereAppending the C-string cstr1a to string str1 gives: Hello Out There .The string str1b is: HelloThe C-string cstr1b is: Out ThereAppending the 1st part of the C-string cstr1b to string str1 gives: Hello Out.The string str2c is: Wide WorldThe appended string str1 is: Hello World.The  string str2d is: WideThe appended string str1d is: Hello Wide .The doubly appended strig str1 is: Hello Wide World .The string str1 appended with exclamations is: Hello !!!!The string str2f is: Wide WorldThe appended string str1 is: Hello World.请按任意键继续. . .*/}//分配新的字符值到字符串的内容void basic_string_assign(void){using namespace std;// The first member function assigning the// characters of a C-string to a stringstring str1a;const char *cstr1a = "Out There";cout << "The C-string cstr1a is: " << cstr1a << "." << endl;str1a.assign(cstr1a);cout << "Assigning the C-string cstr1a to string str1 gives: "<< str1a << "." << endl << endl;// The second member function assigning a specific// number of the of characters a C-string to a stringstring  str1b;const char *cstr1b = "Out There";cout << "The C-string cstr1b is: " << cstr1b << endl;str1b.assign(cstr1b, 3);cout << "Assigning the 1st part of the C-string cstr1b "<< "to string str1 gives: " << str1b << "."<< endl << endl;// The third member function assigning a specific number// of the characters from one string to another string string str1c("Hello "), str2c("Wide World ");cout << "The string str2c is: " << str2c << endl;str1c.assign(str2c, 5, 5);cout << "The newly assigned string str1 is: "<< str1c << "." << endl << endl;// The fourth member function assigning the characters// from one string to another string in two equivalent// ways, comparing the assign and operator =string str1d("Hello"), str2d("Wide"), str3d("World");cout << "The original string str1 is: " << str1d << "." << endl;cout << "The string str2d is: " << str2d << endl;str1d.assign(str2d);cout << "The string str1 newly assigned with string str2d is: "<< str1d << "." << endl;cout << "The string str3d is: " << str3d << "." << endl;str1d = str3d;cout << "The string str1 reassigned with string str3d is: "<< str1d << "." << endl << endl;// The fifth member function assigning a specific // number of characters of a certain value to a stringstring str1e("Hello ");str1e.assign(4, '!');cout << "The string str1 assigned with eclamations is: "<< str1e << endl << endl;// The sixth member function assigning the value from// the range of one string to another stringstring str1f("Hello "), str2f("Wide World ");cout << "The string str2f is: " << str2f << endl;str1f.assign(str2f.begin() + 5, str2f.end() - 1);cout << "The string str1 assigned a range of string str2f is: "<< str1f << "." << endl << endl;return;/*The C-string cstr1a is: Out There.Assigning the C-string cstr1a to string str1 gives: Out There.The C-string cstr1b is: Out ThereAssigning the 1st part of the C-string cstr1b to string str1 gives: Out.The string str2c is: Wide WorldThe newly assigned string str1 is: World.The original string str1 is: Hello.The string str2d is: WideThe string str1 newly assigned with string str2d is: Wide.The string str3d is: World.The string str1 reassigned with string str3d is: World.The string str1 assigned with eclamations is: !!!!The string str2f is: Wide WorldThe string str1 assigned a range of string str2f is: World.请按任意键继续. . .*/}//在返回字符串中指定位置的参考元素void basic_string_at(void){using namespace std;string str1("Hello world"), str2("Goodbye world");const string  cstr1("Hello there"), cstr2("Goodbye now");cout << "The original string str1 is: " << str1 << endl;cout << "The original string str2 is: " << str2 << endl;// Element access to the non const stringsbasic_string <char>::reference refStr1 = str1[6];basic_string <char>::reference refStr2 = str2.at(3);cout << "The character with an index of 6 in string str1 is: "<< refStr1 << "." << endl;cout << "The character with an index of 3 in string str2 is: "<< refStr2 << "." << endl;// Element access to the const stringsbasic_string <char>::const_reference crefStr1 = cstr1[cstr1.length()];basic_string <char>::const_reference crefStr2 = cstr2.at(8);if (crefStr1 == '\0')cout << "The null character is returned as a valid reference."<< endl;elsecout << "The null character is not returned." << endl;cout << "The character with index 8 in the const string cstr2 is: "<< crefStr2 << "." << endl;return;/*The original string str1 is: Hello worldThe original string str2 is: Goodbye worldThe character with an index of 6 in string str1 is: w.The character with an index of 3 in string str2 is: d.The null character is returned as a valid reference.The character with index 8 in the const string cstr2 is: n.请按任意键继续. . .*/}//返回一个迭代解决的第一个元素在字符串中void basic_string_begin(void){using namespace std;string str1("No way out."), str2;basic_string <char>::iterator strp_Iter, str1_Iter, str2_Iter;basic_string <char>::const_iterator str1_cIter;str1_Iter = str1.begin();cout << "The first character of the string str1 is: "<< *str1_Iter << endl;cout << "The full original string str1 is: " << str1 << endl;// The dereferenced iterator can be used to modify a character*str1_Iter = 'G';cout << "The first character of the modified str1 is now: "<< *str1_Iter << endl;cout << "The full modified string str1 is now: " << str1 << endl;// The following line would be an error because iterator is const// *str1_cIter = 'g';// For an empty string, begin is equivalent to endif (str2.begin() == str2.end())cout << "The string str2 is empty." << endl;elsecout << "The string str2 is not empty." << endl;return;/*The first character of the string str1 is: NThe full original string str1 is: No way out.The first character of the modified str1 is now: GThe full modified string str1 is now: Go way out.The string str2 is empty.请按任意键继续. . .*/}//字符串作为C风格的内容转换，空值终止，串void basic_string_c_str(void){using namespace std;string  str1("Hello world");cout << "The original string object str1 is: "<< str1 << endl;cout << "The length of the string object str1 = "<< str1.length() << endl << endl;// Converting a string to an array of charactersconst char *ptr1 = 0;ptr1 = str1.data();cout << "The modified string object ptr1 is: " << ptr1<< endl;cout << "The length of character array str1 = "<< strlen(ptr1) << endl << endl;// Converting a string to a C-style stringconst char *c_str1 = str1.c_str();cout << "The C-style string c_str1 is: " << c_str1<< endl;cout << "The length of C-style string str1 = "<< strlen(c_str1) << endl << endl;return;/*The original string object str1 is: Hello worldThe length of the string object str1 = 11The modified string object ptr1 is: Hello worldThe length of character array str1 = 11The C-style string c_str1 is: Hello worldThe length of C-style string str1 = 11请按任意键继续. . .*/}//返回可存储在一个字符串元素的最大数量不增加串的存储器分配void basic_string_capacity(void){using namespace std;string  str1("Hello world");cout << "The original string str1 is: " << str1 << endl;// The size and length member functions differ in name onlybasic_string <char>::size_type sizeStr1, lenStr1;sizeStr1 = str1.size();lenStr1 = str1.length();basic_string <char>::size_type capStr1, max_sizeStr1;capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a stringcout << "The current size of original string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of original string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of original string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of original string str1 is: "<< max_sizeStr1 << "." << endl << endl;str1.erase(6, 5);cout << "The modified string str1 is: " << str1 << endl;sizeStr1 = str1.size();lenStr1 = str1.length();capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a string// after erasing part of the original stringcout << "The current size of modified string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of modified string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of modified string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of modified string str1 is: "<< max_sizeStr1 << "." << endl;return;/*The original string str1 is: Hello worldThe current size of original string str1 is: 11.The current length of original string str1 is: 11.The capacity of original string str1 is: 15.The max_size of original string str1 is: 4294967294.The modified string str1 is: HelloThe current size of modified string str1 is: 6.The current length of modified string str1 is: 6.The capacity of modified string str1 is: 15.The max_size of modified string str1 is: 4294967294.请按任意键继续. . .*/}//删除字符串中的所有元素void basic_string_clear(void){using namespace std;string  str1("Hello world"), str2;basic_string <char>::iterator str_Iter;cout << "The original string str1 is: ";for (str_Iter = str1.begin(); str_Iter != str1.end(); str_Iter++)cout << *str_Iter;cout << endl;str1.clear();cout << "The modified string str1 is: ";for (str_Iter = str1.begin(); str_Iter != str1.end(); str_Iter++)cout << *str_Iter;cout << endl;//For an empty string, begin is equivalent to endif (str1.begin() == str1.end())cout << "Nothing printed above because "<< "the string str1 is empty." << endl;elsecout << "The string str1 is not empty." << endl;return;/*The original string str1 is: Hello worldThe modified string str1 is:Nothing printed above because the string str1 is empty.请按任意键继续. . .*/}//进行比较以指定字符串的字符串，以确定该两个字符串相等或者如果一个字典顺序小于另一个void basic_string_compare(void){using namespace std;// The first member function compares// an operand string to a parameter stringint comp1;string s1o("CAB");string s1p("CAB");cout << "The operand string is: " << s1o << endl;cout << "The parameter string is: " << s1p << endl;comp1 = s1o.compare(s1p);if (comp1 < 0)cout << "The operand string is less than "<< "the parameter string." << endl;else if (comp1 == 0)cout << "The operand string is equal to "<< "the parameter string." << endl;elsecout << "The operand string is greater than "<< "the parameter string." << endl;cout << endl;// The second member function compares part of// an operand string to a parameter stringint comp2a, comp2b;string s2o("AACAB");string s2p("CAB");cout << "The operand string is: " << s2o << endl;cout << "The parameter string is: " << s2p << endl;comp2a = s2o.compare(2, 3, s2p);if (comp2a < 0)cout << "The last three characters of "<< "the operand string\n are less than "<< "the parameter string." << endl;else if (comp2a == 0)cout << "The last three characters of "<< "the operand string\n are equal to "<< "the parameter string." << endl;elsecout << "The last three characters of "<< "the operand string\n is greater than "<< "the parameter string." << endl;comp2b = s2o.compare(0, 3, s2p);if (comp2b < 0)cout << "The first three characters of "<< "the operand string\n are less than "<< "the parameter string." << endl;else if (comp2b == 0)cout << "The first three characters of "<< "the operand string\n are equal to "<< "the parameter string." << endl;elsecout << "The first three characters of "<< "the operand string\n is greater than "<< "the parameter string." << endl;cout << endl;// The third member function compares part of// an operand string to part of a parameter stringint comp3a;string s3o("AACAB");string s3p("DCABD");cout << "The operand string is: " << s3o << endl;cout << "The parameter string is: " << s3p << endl;comp3a = s3o.compare(2, 3, s3p, 1, 3);if (comp3a < 0)cout << "The three characters from position 2 of "<< "the operand string are less than\n "<< "the 3 characters parameter string "<< "from position 1." << endl;else if (comp3a == 0)cout << "The three characters from position 2 of "<< "the operand string are equal to\n "<< "the 3 characters parameter string "<< "from position 1." << endl;elsecout << "The three characters from position 2 of "<< "the operand string is greater than\n "<< "the 3 characters parameter string "<< "from position 1." << endl;cout << endl;// The fourth member function compares// an operand string to a parameter C-stringint comp4a;string s4o("ABC");const char* cs4p = "DEF";cout << "The operand string is: " << s4o << endl;cout << "The parameter C-string is: " << cs4p << endl;comp4a = s4o.compare(cs4p);if (comp4a < 0)cout << "The operand string is less than "<< "the parameter C-string." << endl;else if (comp4a == 0)cout << "The operand string is equal to "<< "the parameter C-string." << endl;elsecout << "The operand string is greater than "<< "the parameter C-string." << endl;cout << endl;// The fifth member function compares part of// an operand string to a parameter C-stringint comp5a;string s5o("AACAB");const char* cs5p = "CAB";cout << "The operand string is: " << s5o << endl;cout << "The parameter string is: " << cs5p << endl;comp5a = s5o.compare(2, 3, s2p);if (comp5a < 0)cout << "The last three characters of "<< "the operand string\n are less than "<< "the parameter C-string." << endl;else if (comp5a == 0)cout << "The last three characters of "<< "the operand string\n are equal to "<< "the parameter C-string." << endl;elsecout << "The last three characters of "<< "the operand string\n is greater than "<< "the parameter C-string." << endl;cout << endl;// The sixth member function compares part of// an operand string to part of an equal length of// a parameter C-stringint comp6a;string s6o("AACAB");const char* cs6p = "ACAB";cout << "The operand string is: " << s6o << endl;cout << "The parameter C-string is: " << cs6p << endl;comp6a = s6o.compare(1, 3, cs6p, 3);if (comp6a < 0)cout << "The 3 characters from position 1 of "<< "the operand string are less than\n "<< "the first 3 characters of the parameter C-string."<< endl;else if (comp6a == 0)cout << "The 3 characters from position 2 of "<< "the operand string are equal to\n "<< "the first 3 characters of the parameter C-string."<< endl;elsecout << "The 3 characters from position 2 of "<< "the operand string is greater than\n "<< "the first 3 characters of the parameter C-string."<< endl;cout << endl;return;/*The operand string is: CABThe parameter string is: CABThe operand string is equal to the parameter string.The operand string is: AACABThe parameter string is: CABThe last three characters of the operand stringare equal to the parameter string.The first three characters of the operand stringare less than the parameter string.The operand string is: AACABThe parameter string is: DCABDThe three characters from position 2 of the operand string are equal tothe 3 characters parameter string from position 1.The operand string is: ABCThe parameter C-string is: DEFThe operand string is less than the parameter C-string.The operand string is: AACABThe parameter string is: CABThe last three characters of the operand stringare equal to the parameter C-string.The operand string is: AACABThe parameter C-string is: ACABThe 3 characters from position 2 of the operand string are equal tothe first 3 characters of the parameter C-string.请按任意键继续. . .*/}//副本在从源字符串到目标字符数组索引位置最指定数目的字符void basic_string_copy(void){using namespace std;string str1("Hello World");basic_string <char>::iterator str_Iter;char array1[20] = { 0 };char array2[10] = { 0 };basic_string <char>::pointer array1Ptr = array1;basic_string <char>::value_type *array2Ptr = array2;cout << "The original string str1 is: ";for (str_Iter = str1.begin(); str_Iter != str1.end(); str_Iter++)cout << *str_Iter;cout << endl;//basic_string <char>::size_type nArray1;// Note: string::copy is potentially unsafe, consider// using string::_Copy_s instead./*nArray1 = str1.copy(array1Ptr, 12);  // C4996cout << "The number of copied characters in array1 is: "<< nArray1 << endl;cout << "The copied characters array1 is: " << array1 << endl;*///basic_string <char>::size_type nArray2;// Note: string::copy is potentially unsafe, consider// using string::_Copy_s instead./*nArray2 = str1.copy(array2Ptr, 5, 6);  // C4996cout << "The number of copied characters in array2 is: "<< nArray2 << endl;cout << "The copied characters array2 is: " << array2Ptr << endl;*/return;/*编译报错  来自MSDNThe original string str1 is: Hello WorldThe number of copied characters in array1 is: 11The copied characters array1 is: Hello WorldThe number of copied characters in array2 is: 5The copied characters array2 is: World*/}//副本在从源字符串到目标字符数组索引位置最指定数目的字符void basic_string__Copy_s(void){using namespace std;string str1("Hello World");basic_string<char>::iterator str_Iter;const int array1_size = 20;char array1[array1_size] = { 0 };const int array2_size = 10;char array2[array2_size] = { 0 };basic_string<char>::pointer array1Ptr = array1;basic_string<char>::value_type *array2Ptr = array2;cout << "The original string str1 is: ";for (str_Iter = str1.begin(); str_Iter != str1.end(); str_Iter++)cout << *str_Iter;cout << endl;basic_string<char>::size_type nArray1;nArray1 = str1._Copy_s(array1Ptr, array1_size, 12);cout << "The number of copied characters in array1 is: "<< nArray1 << endl;cout << "The copied characters array1 is: " << array1 << endl;basic_string<char>::size_type nArray2;nArray2 = str1._Copy_s(array2Ptr, array2_size, 5, 6);cout << "The number of copied characters in array2 is: "<< nArray2 << endl;cout << "The copied characters array2 is: " << array2Ptr << endl;return;/*The original string str1 is: Hello WorldThe number of copied characters in array1 is: 11The copied characters array1 is: Hello WorldThe number of copied characters in array2 is: 5The copied characters array2 is: World请按任意键继续. . .*/}//字符串的内容转换为字符数组void basic_string_data(void){using namespace std;string str1("Hello world");cout << "The original string object str1 is: "<< str1 << endl;cout << "The length of the string object str1 = "<< str1.length() << endl << endl;// Converting a string to an array of charactersconst char *ptr1 = 0;ptr1 = str1.data();cout << "The modified string object ptr1 is: " << ptr1<< endl;cout << "The length of character array str1 = "<< strlen(ptr1) << endl << endl;// Converting a string to a C-style stringconst char *c_str1 = str1.c_str();cout << "The C-style string c_str1 is: " << c_str1<< endl;cout << "The length of C-style string str1 = "<< strlen(c_str1) << endl << endl;return;/*The original string object str1 is: Hello worldThe length of the string object str1 = 11The modified string object ptr1 is: Hello worldThe length of character array str1 = 11The C-style string c_str1 is: Hello worldThe length of C-style string str1 = 11请按任意键继续. . .*/}//测试该字符串是否是包含的字符或没有void basic_string_empty(void){using namespace std;bool b1, b2;string str1("Hello world");cout << "The original string object str1 is: " << str1 << endl;b1 = str1.empty();if (b1)cout << "The string object str1 is empty." << endl;elsecout << "The string object str1 is not empty." << endl;cout << endl;// An example of an empty string objectstring str2;b2 = str2.empty();if (b2)cout << "The string object str2 is empty." << endl;elsecout << "The string object str2 is not empty." << endl;return;/*The original string object str1 is: Hello worldThe string object str1 is not empty.The string object str2 is empty.请按任意键继续. . .*/}//返回地址字符串中的成功的最后一个元素的位置的迭代器void basic_string_end(void){using namespace std;string str1("No way out."), str2;basic_string <char>::iterator str_Iter, str1_Iter, str2_Iter;basic_string <char>::const_iterator str1_cIter;str1_Iter = str1.end();str1_Iter--;str1_Iter--;cout << "The last character-letter of the string str1 is: " << *str1_Iter << endl;cout << "The full orginal string str1 is: " << str1 << endl;// end used to test when an iterator has reached the end of its stringcout << "The string is now: ";for (str_Iter = str1.begin(); str_Iter != str1.end(); str_Iter++)cout << *str_Iter;cout << endl;// The dereferenced iterator can be used to modify a character*str1_Iter = 'T';cout << "The last character-letter of the modified str1 is now: "<< *str1_Iter << endl;cout << "The modified string str1 is now: " << str1 << endl;// The following line would be an error because iterator is const// *str1_cIter = 'T';// For an empty string, end is equivalent to beginif (str2.begin() == str2.end())cout << "The string str2 is empty." << endl;elsecout << "The stringstr2  is not empty." << endl;return;/*The last character-letter of the string str1 is: tThe full orginal string str1 is: No way out.The string is now: No way out.The last character-letter of the modified str1 is now: TThe modified string str1 is now: No way ouT.The string str2 is empty.请按任意键继续. . .*/}//删除从指定位置的元素或一个范围中的字符串的元素的void basic_string_erase(void){using namespace std;// The 1st member function using a range demarcated// by iteratorsstring str1("Hello world");basic_string <char>::iterator str1_Iter;cout << "The original string object str1 is: "<< str1 << "." << endl;str1_Iter = str1.erase(str1.begin() + 3, str1.end() - 1);cout << "The first element after those removed is: "<< *str1_Iter << "." << endl;cout << "The modified string object str1 is: " << str1<< "." << endl << endl;// The 2nd member function erasing a char pointed to // by an iteratorstring str2("Hello World");basic_string <char>::iterator str2_Iter;cout << "The original string object str2 is: " << str2<< "." << endl;str2_Iter = str2.erase(str2.begin() + 5);cout << "The first element after those removed is: "<< *str2_Iter << "." << endl;cout << "The modified string object str2 is: " << str2<< "." << endl << endl;// The 3rd member function erasing a number of chars // after a charstring str3("Hello computer"), str3m;basic_string <char>::iterator str3_Iter;cout << "The original string object str3 is: "<< str3 << "." << endl;str3m = str3.erase(6, 8);cout << "The modified string object str3m is: "<< str3m << "." << endl;return;/*The original string object str1 is: Hello world.The first element after those removed is: d.The modified string object str1 is: Held.The original string object str2 is: Hello World.The first element after those removed is: W.The modified string object str2 is: HelloWorld.The original string object str3 is: Hello computer.The modified string object str3m is: Hello .请按任意键继续. . .*/}//搜索在前进方向的字符串为一个字符串的第一个出现的字符的指定序列相匹配void basic_string_find(void){using namespace std;// The first member function// searches for a single character in a stringstring str1("Hello Everyone");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type indexCh1a, indexCh1b;indexCh1a = str1.find("e", 3);if (indexCh1a != string::npos)cout << "The index of the 1st 'e' found after the 3rd"<< " position in str1 is: " << indexCh1a << endl;elsecout << "The character 'e' was not found in str1 ." << endl;indexCh1b = str1.find("x");if (indexCh1b != string::npos)cout << "The index of the 'x' found in str1 is: "<< indexCh1b << endl << endl;elsecout << "The Character 'x' was not found in str1."<< endl << endl;// The second member function searches a string// for a substring as specified by a C-stringstring str2("Let me make this perfectly clear.");cout << "The original string str2 is: " << str2 << endl;basic_string <char>::size_type indexCh2a, indexCh2b;const char *cstr2 = "perfect";indexCh2a = str2.find(cstr2, 5);if (indexCh2a != string::npos)cout << "The index of the 1st element of 'perfect' "<< "after\n the 5th position in str2 is: "<< indexCh2a << endl;elsecout << "The substring 'perfect' was not found in str2 ."<< endl;const char *cstr2b = "imperfectly";indexCh2b = str2.find(cstr2b, 0);if (indexCh2b != string::npos)cout << "The index of the 1st element of 'imperfect' "<< "after\n the 5th position in str3 is: "<< indexCh2b << endl;elsecout << "The substring 'imperfect' was not found in str2 ."<< endl << endl;// The third member function searches a string// for a substring as specified by a C-stringstring str3("This is a sample string for this program");cout << "The original string str3 is: " << str3 << endl;basic_string <char>::size_type indexCh3a, indexCh3b;const char *cstr3a = "sample";indexCh3a = str3.find(cstr3a);if (indexCh3a != string::npos)cout << "The index of the 1st element of sample "<< "in str3 is: " << indexCh3a << endl;elsecout << "The substring 'perfect' was not found in str3 ."<< endl;const char *cstr3b = "for";indexCh3b = str3.find(cstr3b, indexCh3a + 1, 2);if (indexCh3b != string::npos)cout << "The index of the next occurrence of 'for' is in "<< "str3 begins at: " << indexCh3b << endl << endl;elsecout << "There is no next occurrence of 'for' in str3 ."<< endl << endl;// The fourth member function searches a string// for a substring as specified by a stringstring str4("clearly this perfectly unclear.");cout << "The original string str4 is: " << str4 << endl;basic_string <char>::size_type indexCh4a, indexCh4b;string str4a("clear");indexCh4a = str4.find(str4a, 5);if (indexCh4a != string::npos)cout << "The index of the 1st element of 'clear' "<< "after\n the 5th position in str4 is: "<< indexCh4a << endl;elsecout << "The substring 'clear' was not found in str4 ."<< endl;string str4b("clear");indexCh4b = str4.find(str4b);if (indexCh4b != string::npos)cout << "The index of the 1st element of 'clear' "<< "in str4 is: "<< indexCh4b << endl;elsecout << "The substring 'clear' was not found in str4 ."<< endl << endl;return;/*The original string str1 is: Hello EveryoneThe index of the 1st 'e' found after the 3rd position in str1 is: 8The Character 'x' was not found in str1.The original string str2 is: Let me make this perfectly clear.The index of the 1st element of 'perfect' afterthe 5th position in str2 is: 17The substring 'imperfect' was not found in str2 .The original string str3 is: This is a sample string for this programThe index of the 1st element of sample in str3 is: 10The index of the next occurrence of 'for' is in str3 begins at: 24The original string str4 is: clearly this perfectly unclear.The index of the 1st element of 'clear' afterthe 5th position in str4 is: 25The index of the 1st element of 'clear' in str4 is: 0请按任意键继续. . .*/}//通过搜索的第一个字符的字符串不是指定字符串的任何元素void basic_string_find_first_not_of(void){using namespace std;// The first member function// searches for a single character in a stringstring str1("xddd-1234-abcd");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type indexCh1a, indexCh1b;static const basic_string <char>::size_type npos = -1;indexCh1a = str1.find_first_not_of("d", 2);if (indexCh1a != npos)cout << "The index of the 1st 'd' found after the 3rd"<< " position in str1 is: " << indexCh1a << endl;elsecout << "The character 'd' was not found in str1 ." << endl;indexCh1b = str1.find_first_not_of("x");if (indexCh1b != npos)cout << "The index of the 'non x' found in str1 is: "<< indexCh1b << endl << endl;elsecout << "The character 'non x' was not found in str1."<< endl << endl;// The second member function searches a string// for a substring as specified by a C-stringstring str2("BBB-1111");cout << "The original string str2 is: " << str2 << endl;basic_string <char>::size_type indexCh2a, indexCh2b;const char *cstr2 = "B1";indexCh2a = str2.find_first_not_of(cstr2, 6);if (indexCh2a != npos)cout << "The index of the 1st occurrence of an "<< "element of 'B1' in str2 after\n the 6th "<< "position is: " << indexCh2a << endl;elsecout << "Elements of the substring 'B1' were not"<< "\n found in str2 after the 6th position."<< endl;const char *cstr2b = "B2";indexCh2b = str2.find_first_not_of(cstr2b);if (indexCh2b != npos)cout << "The index of the 1st element of 'B2' "<< "after\n the 0th position in str2 is: "<< indexCh2b << endl << endl;elsecout << "The substring 'B2' was not found in str2 ."<< endl << endl << endl;// The third member function searches a string// for a substring as specified by a C-stringstring str3("444-555-GGG");cout << "The original string str3 is: " << str3 << endl;basic_string <char>::size_type indexCh3a, indexCh3b;const char *cstr3a = "45G";indexCh3a = str3.find_first_not_of(cstr3a);if (indexCh3a != npos)cout << "The index of the 1st occurrence of an "<< "element in str3\n other than one of the "<< "characters in '45G' is: " << indexCh3a<< endl;elsecout << "Elements in str3 contain only characters "<< " in the string '45G'. "<< endl;const char *cstr3b = "45G";indexCh3b = str3.find_first_not_of(cstr3b, indexCh3a + 1, 2);if (indexCh3b != npos)cout << "The index of the second occurrence of an "<< "element of '45G' in str3\n after the 0th "<< "position is: " << indexCh3b << endl << endl;elsecout << "Elements in str3 contain only characters "<< " in the string  '45G'. "<< endl << endl;// The fourth member function searches a string// for a substring as specified by a stringstring str4("12-ab-12-ab");cout << "The original string str4 is: " << str4 << endl;basic_string <char>::size_type indexCh4a, indexCh4b;string str4a("ba3");indexCh4a = str4.find_first_not_of(str4a, 5);if (indexCh4a != npos)cout << "The index of the 1st non occurrence of an "<< "element of 'ba3' in str4 after\n the 5th "<< "position is: " << indexCh4a << endl;elsecout << "Elements other than those in the substring"<< " 'ba3' were not found in the string str4."<< endl;string str4b("12");indexCh4b = str4.find_first_not_of(str4b);if (indexCh4b != npos)cout << "The index of the 1st non occurrence of an "<< "element of '12' in str4 after\n the 0th "<< "position is: " << indexCh4b << endl;elsecout << "Elements other than those in the substring"<< " '12' were not found in the string str4."<< endl;return;/*The original string str1 is: xddd-1234-abcdThe index of the 1st 'd' found after the 3rd position in str1 is: 4The index of the 'non x' found in str1 is: 1The original string str2 is: BBB-1111Elements of the substring 'B1' were notfound in str2 after the 6th position.The index of the 1st element of 'B2' afterthe 0th position in str2 is: 3The original string str3 is: 444-555-GGGThe index of the 1st occurrence of an element in str3other than one of the characters in '45G' is: 3The index of the second occurrence of an element of '45G' in str3after the 0th position is: 7The original string str4 is: 12-ab-12-abThe index of the 1st non occurrence of an element of 'ba3' in str4 afterthe 5th position is: 5The index of the 1st non occurrence of an element of '12' in str4 afterthe 0th position is: 2请按任意键继续. . .*/}//通过搜索的第一个字符的字符串指定字符串的任何元素相匹配void basic_string_find_first_of(void){using namespace std;// The first member function// searches for a single character in a stringstring str1("abcd-1234-abcd-1234");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type indexCh1a, indexCh1b;static const basic_string <char>::size_type npos = -1;indexCh1a = str1.find_first_of("d", 5);if (indexCh1a != npos)cout << "The index of the 1st 'd' found after the 5rd"<< " position in str1 is: " << indexCh1a << endl;elsecout << "The character 'd' was not found in str1 ." << endl;indexCh1b = str1.find_first_of("x");if (indexCh1b != npos)cout << "The index of the 'x' found in str1 is: "<< indexCh1b << endl << endl;elsecout << "The character 'x' was not found in str1."<< endl << endl;// The second member function searches a string// for a substring as specified by a C-stringstring str2("ABCD-1234-ABCD-1234");cout << "The original string str2 is: " << str2 << endl;basic_string <char>::size_type indexCh2a, indexCh2b;const char *cstr2 = "B1";indexCh2a = str2.find_first_of(cstr2, 6);if (indexCh2a != npos)cout << "The index of the 1st occurrence of an "<< "element of 'B1' in str2 after\n the 6th "<< "position is: " << indexCh2a << endl;elsecout << "Elements of the substring 'B1' were not "<< "found in str2 after the 10th position."<< endl;const char *cstr2b = "D2";indexCh2b = str2.find_first_of(cstr2b);if (indexCh2b != npos)cout << "The index of the 1st element of 'D2' "<< "after\n the 0th position in str2 is: "<< indexCh2b << endl << endl;elsecout << "The substring 'D2' was not found in str2 ."<< endl << endl << endl;// The third member function searches a string// for a substring as specified by a C-stringstring str3("123-abc-123-abc-456-EFG-456-EFG");cout << "The original string str3 is: " << str3 << endl;basic_string <char>::size_type indexCh3a, indexCh3b;const char *cstr3a = "5G";indexCh3a = str3.find_first_of(cstr3a);if (indexCh3a != npos)cout << "The index of the 1st occurrence of an "<< "element of '5G' in str3 after\n the 0th "<< "position is: " << indexCh3a << endl;elsecout << "Elements of the substring '5G' were not "<< "found in str3\n after the 0th position."<< endl;const char *cstr3b = "5GF";indexCh3b = str3.find_first_of(cstr3b, indexCh3a + 1, 2);if (indexCh3b != npos)cout << "The index of the second occurrence of an "<< "element of '5G' in str3\n after the 0th "<< "position is: " << indexCh3b << endl << endl;elsecout << "Elements of the substring '5G' were not "<< "found in str3\n after the first occurrrence."<< endl << endl;// The fourth member function searches a string// for a substring as specified by a stringstring str4("12-ab-12-ab");cout << "The original string str4 is: " << str4 << endl;basic_string <char>::size_type indexCh4a, indexCh4b;string str4a("ba3");indexCh4a = str4.find_first_of(str4a, 5);if (indexCh4a != npos)cout << "The index of the 1st occurrence of an "<< "element of 'ba3' in str4 after\n the 5th "<< "position is: " << indexCh4a << endl;elsecout << "Elements of the substring 'ba3' were not "<< "found in str4\n after the 0th position."<< endl;string str4b("a2");indexCh4b = str4.find_first_of(str4b);if (indexCh4b != npos)cout << "The index of the 1st occurrence of an "<< "element of 'a2' in str4 after\n the 0th "<< "position is: " << indexCh4b << endl;elsecout << "Elements of the substring 'a2' were not "<< "found in str4\n after the 0th position."<< endl;return;/*The original string str1 is: abcd-1234-abcd-1234The index of the 1st 'd' found after the 5rd position in str1 is: 13The character 'x' was not found in str1.The original string str2 is: ABCD-1234-ABCD-1234The index of the 1st occurrence of an element of 'B1' in str2 afterthe 6th position is: 11The index of the 1st element of 'D2' afterthe 0th position in str2 is: 3The original string str3 is: 123-abc-123-abc-456-EFG-456-EFGThe index of the 1st occurrence of an element of '5G' in str3 afterthe 0th position is: 17The index of the second occurrence of an element of '5G' in str3after the 0th position is: 22The original string str4 is: 12-ab-12-abThe index of the 1st occurrence of an element of 'ba3' in str4 afterthe 5th position is: 9The index of the 1st occurrence of an element of 'a2' in str4 afterthe 0th position is: 1请按任意键继续. . .*/}//通过搜索的最后一个字符的字符串不是指定字符串的任何元素void basic_string_find_last_not_of(void){using namespace std;// The first member function// searches for a single character in a stringstring str1("dddd-1dd4-abdd");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type indexCh1a, indexCh1b;static const basic_string <char>::size_type npos = -1;indexCh1a = str1.find_last_not_of("d", 7);if (indexCh1a != npos)cout << "The index of the last non 'd'\n found before the "<< "7th position in str1 is: " << indexCh1a << endl;elsecout << "The non 'd' character was not found ." << endl;indexCh1b = str1.find_last_not_of("d");if (indexCh1b != npos)cout << "The index of the non 'd' found in str1 is: "<< indexCh1b << endl << endl;elsecout << "The Character 'non x' was not found in str1."<< endl << endl;// The second member function searches a string// for a substring as specified by a C-stringstring str2("BBB-1111");cout << "The original string str2 is: " << str2 << endl;basic_string <char>::size_type indexCh2a, indexCh2b;const char *cstr2 = "B1";indexCh2a = str2.find_last_not_of(cstr2, 6);if (indexCh2a != npos)cout << "The index of the last occurrence of a "<< "element\n not of 'B1' in str2 before the 6th "<< "position is: " << indexCh2a << endl;elsecout << "Elements not of the substring 'B1' were not "<< "\n found in str2 before the 6th position."<< endl;const char *cstr2b = "B-1";indexCh2b = str2.find_last_not_of(cstr2b);if (indexCh2b != npos)cout << "The index of the last element not "<< "in 'B-1'\n is: "<< indexCh2b << endl << endl;elsecout << "The elements of the substring 'B-1' were "<< "not found in str2 ."<< endl << endl;// The third member function searches a string// for a substring as specified by a C-stringstring str3("444-555-GGG");cout << "The original string str3 is: " << str3 << endl;basic_string <char>::size_type indexCh3a, indexCh3b;const char *cstr3a = "45G";indexCh3a = str3.find_last_not_of(cstr3a);if (indexCh3a != npos)cout << "The index of the last occurrence of an "<< "element in str3\n other than one of the "<< "characters in '45G' is: " << indexCh3a<< endl;elsecout << "Elements in str3 contain only characters "<< " in the string  '45G'. "<< endl;const char *cstr3b = "45G";indexCh3b = str3.find_last_not_of(cstr3b, 6, indexCh3a - 1);if (indexCh3b != npos)cout << "The index of the penultimate occurrence of an "<< "element\n not in '45G' in str3 is: "<< indexCh3b << endl << endl;elsecout << "Elements in str3 contain only characters "<< " in the string '45G'. "<< endl << endl;// The fourth member function searches a string// for a substring as specified by a stringstring str4("12-ab-12-ab");cout << "The original string str4 is: " << str4 << endl;basic_string <char>::size_type indexCh4a, indexCh4b;string str4a("b-a");indexCh4a = str4.find_last_not_of(str4a, 5);if (indexCh4a != npos)cout << "The index of the last occurrence of an "<< "element not\n in 'b-a' in str4 before the 5th "<< "position is: " << indexCh4a << endl;elsecout << "Elements other than those in the substring"<< " 'b-a' were not found in the string str4."<< endl;string str4b("12");indexCh4b = str4.find_last_not_of(str4b);if (indexCh4b != npos)cout << "The index of the last occurrence of an "<< "element not in '12'\n in str4 before the end "<< "position is: " << indexCh4b << endl;elsecout << "Elements other than those in the substring"<< " '12'\n were not found in the string str4."<< endl;return;/*The original string str1 is: dddd-1dd4-abddThe index of the last non 'd'found before the 7th position in str1 is: 5The index of the non 'd' found in str1 is: 11The original string str2 is: BBB-1111The index of the last occurrence of a elementnot of 'B1' in str2 before the 6th position is: 3The elements of the substring 'B-1' were not found in str2 .The original string str3 is: 444-555-GGGThe index of the last occurrence of an element in str3other than one of the characters in '45G' is: 7The index of the penultimate occurrence of an elementnot in '45G' in str3 is: 3The original string str4 is: 12-ab-12-abThe index of the last occurrence of an element notin 'b-a' in str4 before the 5th position is: 1The index of the last occurrence of an element not in '12'in str4 before the end position is: 10请按任意键继续. . .*/}//通过搜索的最后一个字符字符串，是一个指定字符串的元素void basic_string_find_last_of(void){using namespace std;// The first member function// searches for a single character in a stringstring str1("abcd-1234-abcd-1234");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type indexCh1a, indexCh1b;static const basic_string <char>::size_type npos = -1;indexCh1a = str1.find_last_of("d", 14);if (indexCh1a != npos)cout << "The index of the last 'd' found before the 14th"<< " position in str1 is: " << indexCh1a << endl;elsecout << "The character 'd' was not found in str1 ." << endl;indexCh1b = str1.find_first_of("x");if (indexCh1b != npos)cout << "The index of the 'x' found in str1 is: "<< indexCh1b << endl << endl;elsecout << "The character 'x' was not found in str1."<< endl << endl;// The second member function searches a string// for a substring as specified by a C-stringstring str2("ABCD-1234-ABCD-1234");cout << "The original string str2 is: " << str2 << endl;basic_string <char>::size_type indexCh2a, indexCh2b;const char *cstr2 = "B1";indexCh2a = str2.find_last_of(cstr2, 12);if (indexCh2a != npos)cout << "The index of the last occurrence of an "<< "element of 'B1' in str2 before\n the 12th "<< "position is: " << indexCh2a << endl;elsecout << "Elements of the substring 'B1' were not "<< "found in str2 before the 12th position."<< endl;const char *cstr2b = "D2";indexCh2b = str2.find_last_of(cstr2b);if (indexCh2b != npos)cout << "The index of the last element of 'D2' "<< "after\n the 0th position in str2 is: "<< indexCh2b << endl << endl;elsecout << "The substring 'D2' was not found in str2 ."<< endl << endl << endl;// The third member function searches a string// for a substring as specified by a C-stringstring str3("456-EFG-456-EFG");cout << "The original string str3 is: " << str3 << endl;basic_string <char>::size_type indexCh3a;const char *cstr3a = "5E";indexCh3a = str3.find_last_of(cstr3a, 8, 8);if (indexCh3a != npos)cout << "The index of the last occurrence of an "<< "element of '5E' in str3 before\n the 8th "<< "position is: " << indexCh3a << endl << endl;elsecout << "Elements of the substring '5G' were not "<< "found in str3\n before the 8th position."<< endl << endl;// The fourth member function searches a string// for a substring as specified by a stringstring str4("12-ab-12-ab");cout << "The original string str4 is: " << str4 << endl;basic_string <char>::size_type indexCh4a, indexCh4b;string str4a("ba3");indexCh4a = str4.find_last_of(str4a, 8);if (indexCh4a != npos)cout << "The index of the last occurrence of an "<< "element of 'ba3' in str4 before\n the 8th "<< "position is: " << indexCh4a << endl;elsecout << "Elements of the substring 'ba3' were not "<< "found in str4\n after the 0th position."<< endl;string str4b("a2");indexCh4b = str4.find_last_of(str4b);if (indexCh4b != npos)cout << "The index of the last occurrence of an "<< "element of 'a2' in str4 before\n the 0th "<< "position is: " << indexCh4b << endl;elsecout << "Elements of the substring 'a2' were not "<< "found in str4\n after the 0th position."<< endl;return;/*The original string str1 is: abcd-1234-abcd-1234The index of the last 'd' found before the 14th position in str1 is: 1The character 'x' was not found in str1.The original string str2 is: ABCD-1234-ABCD-1234The index of the last occurrence of an element of 'B1' in str2 beforethe 12th position is: 11The index of the last element of 'D2' afterthe 0th position in str2 is: 16The original string str3 is: 456-EFG-456-EFGThe index of the last occurrence of an element of '5E' in str3 beforethe 8th position is: 4The original string str4 is: 12-ab-12-abThe index of the last occurrence of an element of 'ba3' in str4 beforethe 8th position is: 4The index of the last occurrence of an element of 'a2' in str4 beforethe 0th position is: 9请按任意键继续. . .*/}//返回分配器对象的副本，用于构造串void basic_string_get_allocator(void){using namespace std;// The following lines declare objects// that use the default allocator.string s1;basic_string <char> s2;basic_string <char, char_traits< char >, allocator< char > > s3;// s4 will use the same allocator class as s1basic_string <char> s4(s1.get_allocator());basic_string <char>::allocator_type xchar = s1.get_allocator();// You can now call functions on the allocator class xchar used by s1return;}//在插入指定位置的元素或多个元素或者一个范围元素融入串void basic_string_insert(void){using namespace std;// The first member function inserting a C-string// at a given positionbasic_string <char> str1a("way");const char *cstr1a = "a";str1a.insert(0, cstr1a);cout << "The string with a C-string inserted at position 0 is: "<< str1a << "." << endl;// The second member function inserting a C-string// at a given position for a specified number of elementsbasic_string <char> str2a("Good");const char *cstr2a = "Bye Bye Baby";str2a.insert(4, cstr2a, 3);cout << "The string with a C-string inserted at the end is: "<< str2a << "." << endl;// The third member function inserting a string// at a given positionbasic_string <char> str3a("Bye");string str3b("Good");str3a.insert(0, str3b);cout << "The string with a string inserted at position 0 is: "<< str3a << "." << endl;// The fourth member function inserting part of// a string at a given positionbasic_string <char> str4a("Good ");string str4b("Bye Bye Baby");str4a.insert(5, str4b, 8, 4);cout << "The string with part of a string inserted at position 4 is: "<< str4a << "." << endl;// The fifth member function inserts a number of characters// at a specified position in the stringstring str5("The number is: .");str5.insert(15, 3, '3');cout << "The string with characters inserted is: "<< str5 << endl;// The sixth member function inserts a character// at a specified position in the stringstring str6("ABCDFG");basic_string <char>::iterator str6_Iter = (str6.begin() + 4);str6.insert(str6_Iter, 'e');cout << "The string with a character inserted is: "<< str6 << endl;// The seventh member function inserts a range// at a specified position in the stringstring str7a("ABCDHIJ");string str7b("abcdefgh");basic_string <char>::iterator str7a_Iter = (str7a.begin() + 4);str7a.insert(str7a_Iter, str7b.begin() + 4, str7b.end() - 1);cout << "The string with a character inserted from a range is: "<< str7a << endl;// The eigth member function inserts a number of// characters at a specified position in the stringstring str8("ABCDHIJ");basic_string <char>::iterator str8_Iter = (str8.begin() + 4);str8.insert(str8_Iter, 3, 'e');cout << "The string with a character inserted from a range is: "<< str8 << endl;return;/*The string with a C-string inserted at position 0 is: away.The string with a C-string inserted at the end is: GoodBye.The string with a string inserted at position 0 is: GoodBye.The string with part of a string inserted at position 4 is: Good Baby.The string with characters inserted is: The number is: 333.The string with a character inserted is: ABCDeFGThe string with a character inserted from a range is: ABCDefgHIJThe string with a character inserted from a range is: ABCDeeeHIJ请按任意键继续. . .*/}//返回字符串中的元素的当前数目void basic_string_length(void){using namespace std;string str1("Hello world");cout << "The original string str1 is: " << str1 << endl;// The size and length member functions differ in name onlybasic_string <char>::size_type sizeStr1, lenStr1;sizeStr1 = str1.size();lenStr1 = str1.length();basic_string <char>::size_type capStr1, max_sizeStr1;capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a stringcout << "The current size of original string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of original string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of original string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of original string str1 is: "<< max_sizeStr1 << "." << endl << endl;str1.erase(6, 5);cout << "The modified string str1 is: " << str1 << endl;sizeStr1 = str1.size();lenStr1 = str1.length();capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a string// after erasing part of the original stringcout << "The current size of modified string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of modified string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of modified string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of modified string str1 is: "<< max_sizeStr1 << "." << endl;return;/*The original string str1 is: Hello worldThe current size of original string str1 is: 11.The current length of original string str1 is: 11.The capacity of original string str1 is: 15.The max_size of original string str1 is: 4294967294.The modified string str1 is: HelloThe current size of modified string str1 is: 6.The current length of modified string str1 is: 6.The capacity of modified string str1 is: 15.The max_size of modified string str1 is: 4294967294.请按任意键继续. . .*/}//返回一个字符串应该包含字符的最大数量void basic_string_max_size(void){using namespace std;string str1("Hello world");cout << "The original string str1 is: " << str1 << endl;// The size and length member functions differ in name onlybasic_string <char>::size_type sizeStr1, lenStr1;sizeStr1 = str1.size();lenStr1 = str1.length();basic_string <char>::size_type capStr1, max_sizeStr1;capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a stringcout << "The current size of original string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of original string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of original string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of original string str1 is: "<< max_sizeStr1 << "." << endl << endl;str1.erase(6, 5);cout << "The modified string str1 is: " << str1 << endl;sizeStr1 = str1.size();lenStr1 = str1.length();capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a string// after erasing part of the original stringcout << "The current size of modified string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of modified string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of modified string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of modified string str1 is: "<< max_sizeStr1 << "." << endl;return;/*The original string str1 is: Hello worldThe current size of original string str1 is: 11.The current length of original string str1 is: 11.The capacity of original string str1 is: 15.The max_size of original string str1 is: 4294967294.The modified string str1 is: HelloThe current size of modified string str1 is: 6.The current length of modified string str1 is: 6.The capacity of modified string str1 is: 15.The max_size of modified string str1 is: 4294967294.请按任意键继续. . .*/}//将一个元素添加到字符串的末尾void basic_string_push_back(void){using namespace std;string str1("abc");basic_string <char>::iterator str_Iter, str1_Iter;cout << "The original string str1 is: ";for (str_Iter = str1.begin(); str_Iter != str1.end(); str_Iter++)cout << *str_Iter;cout << endl;// str1.push_back ( 'd' );str1_Iter = str1.end();str1_Iter--;cout << "The last character-letter of the modified str1 is now: "<< *str1_Iter << endl;cout << "The modified string str1 is: ";for (str_Iter = str1.begin(); str_Iter != str1.end(); str_Iter++)cout << *str_Iter;cout << endl;return;/*The original string str1 is: abcThe last character-letter of the modified str1 is now: cThe modified string str1 is: abc请按任意键继续. . .*/}//返回一个迭代器的第一个元素的字符串逆转void basic_string_rbegin(void){using namespace std;string str1("Able was I ere I saw Elba"), str2;basic_string <char>::reverse_iterator str_rIter, str1_rIter, str2_rIter;basic_string <char>::const_reverse_iterator str1_rcIter;str1_rIter = str1.rbegin();// str1_rIter--;cout << "The first character-letter of the reversed string str1 is: "<< *str1_rIter << endl;cout << "The full reversed string str1 is:\n ";for (str_rIter = str1.rbegin(); str_rIter != str1.rend(); str_rIter++)cout << *str_rIter;cout << endl;// The dereferenced iterator can be used to modify a character*str1_rIter = 'A';cout << "The first character-letter of the modified str1 is now: "<< *str1_rIter << endl;cout << "The full modified reversed string str1 is now:\n ";for (str_rIter = str1.rbegin(); str_rIter != str1.rend(); str_rIter++)cout << *str_rIter;cout << endl;// The following line would be an error because iterator is const// *str1_rcIter = 'A';// For an empty string, begin is equivalent to endif (str2.rbegin() == str2.rend())cout << "The string str2 is empty." << endl;elsecout << "The stringstr2  is not empty." << endl;return;/*The first character-letter of the reversed string str1 is: aThe full reversed string str1 is:ablE was I ere I saw elbAThe first character-letter of the modified str1 is now: AThe full modified reversed string str1 is now:AblE was I ere I saw elbAThe string str2 is empty.请按任意键继续. . .*/}//返回一个指向刚刚超越了逆转字符串中的最后一个元素的迭代void basic_string_rend(void){using namespace std;string str1("Able was I ere I saw Elba"), str2;basic_string <char>::reverse_iterator str_rIter, str1_rIter, str2_rIter;basic_string <char>::const_reverse_iterator str1_rcIter;str1_rIter = str1.rend();str1_rIter--;cout << "The last character-letter of the reversed string str1 is: "<< *str1_rIter << endl;cout << "The full reversed string str1 is:\n ";for (str_rIter = str1.rbegin(); str_rIter != str1.rend(); str_rIter++)cout << *str_rIter;cout << endl;// The dereferenced iterator can be used to modify a character*str1_rIter = 'o';cout << "The last character-letter of the modified str1 is now: "<< *str1_rIter << endl;cout << "The full modified reversed string str1 is now:\n ";for (str_rIter = str1.rbegin(); str_rIter != str1.rend(); str_rIter++)cout << *str_rIter;cout << endl;// The following line would be an error because iterator is const// *str1_rcIter = 'T';// For an empty string, end is equivalent to beginif (str2.rbegin() == str2.rend())cout << "The string str2 is empty." << endl;elsecout << "The stringstr2  is not empty." << endl;return;/*The last character-letter of the reversed string str1 is: AThe full reversed string str1 is:ablE was I ere I saw elbAThe last character-letter of the modified str1 is now: oThe full modified reversed string str1 is now:ablE was I ere I saw elboThe string str2 is empty.请按任意键继续. . .*/}//在一个字符串替换元素的指定位置与来自其它范围或字符串或C字符串复制指定的字符或字符void basic_string_replace(void){using namespace std;// The first two member functions replace// part of the operand string with// characters from a parameter string or C-stringstring result1a, result1b;string s1o("AAAAAAAA");string s1p("BBB");const char* cs1p = "CCC";cout << "The operand string s1o is: " << s1o << endl;cout << "The parameter string s1p is: " << s1p << endl;cout << "The parameter C-string cs1p is: " << cs1p << endl;result1a = s1o.replace(1, 3, s1p);cout << "The result of s1o.replace ( 1 , 3 , s1p )\n is "<< "the string: " << result1a << "." << endl;result1b = s1o.replace(5, 3, cs1p);cout << "The result of s1o.replace ( 5 , 3 , cs1p )\n is "<< "the string: " << result1b << "." << endl;cout << endl;// The third & fourth member function replace// part of the operand string with characters// form part of a parameter string or C-stringstring result2a, result2b;string s2o("AAAAAAAA");string s2p("BBB");const char* cs2p = "CCC";cout << "The operand string s2o is: " << s2o << endl;cout << "The parameter string s1p is: " << s2p << endl;cout << "The parameter C-string cs2p is: " << cs2p << endl;result2a = s2o.replace(1, 3, s2p, 1, 2);cout << "The result of s2o.replace (1, 3, s2p, 1, 2)\n is "<< "the string: " << result2a << "." << endl;result2b = s2o.replace(4, 3, cs2p, 1);cout << "The result of s2o.replace (4 ,3 ,cs2p)\n is "<< "the string: " << result2b << "." << endl;cout << endl;// The fifth member function replaces// part of the operand string with charactersstring result3a;string s3o("AAAAAAAA");char ch3p = 'C';cout << "The operand string s3o is: " << s3o << endl;cout << "The parameter character c1p is: " << ch3p << endl;result3a = s3o.replace(1, 3, 4, ch3p);cout << "The result of s3o.replace(1, 3, 4, ch3p)\n is "<< "the string: " << result3a << "." << endl;cout << endl;// The sixth & seventh member functions replace// part of the operand string, delineated with iterators,// with a parameter string or C-stringstring s4o("AAAAAAAA");string s4p("BBB");const char* cs4p = "CCC";cout << "The operand string s4o is: " << s4o << endl;cout << "The parameter string s4p is: " << s4p << endl;cout << "The parameter C-string cs4p is: " << cs4p << endl;basic_string<char>::iterator IterF0, IterL0;IterF0 = s4o.begin();IterL0 = s4o.begin() + 3;string result4a, result4b;result4a = s4o.replace(IterF0, IterL0, s4p);cout << "The result of s1o.replace (IterF0, IterL0, s4p)\n is "<< "the string: " << result4a << "." << endl;result4b = s4o.replace(IterF0, IterL0, cs4p);cout << "The result of s4o.replace (IterF0, IterL0, cs4p)\n is "<< "the string: " << result4b << "." << endl;cout << endl;// The 8th member function replaces// part of the operand string delineated with iterators// with a number of characters from a parameter C-stringstring s5o("AAAAAAAF");const char* cs5p = "CCCBB";cout << "The operand string s5o is: " << s5o << endl;cout << "The parameter C-string cs5p is: " << cs5p << endl;basic_string<char>::iterator IterF1, IterL1;IterF1 = s5o.begin();IterL1 = s5o.begin() + 4;string result5a;result5a = s5o.replace(IterF1, IterL1, cs5p, 4);cout << "The result of s5o.replace (IterF1, IterL1, cs4p ,4)\n is "<< "the string: " << result5a << "." << endl;cout << endl;// The 9th member function replaces// part of the operand string delineated with iterators// with specified charactersstring s6o("AAAAAAAG");char ch6p = 'q';cout << "The operand string s6o is: " << s6o << endl;cout << "The parameter character ch6p is: " << ch6p << endl;basic_string<char>::iterator IterF2, IterL2;IterF2 = s6o.begin();IterL2 = s6o.begin() + 3;string result6a;result6a = s6o.replace(IterF2, IterL2, 4, ch6p);cout << "The result of s6o.replace (IterF1, IterL1, 4, ch6p)\n is "<< "the string: " << result6a << "." << endl;cout << endl;// The 10th member function replaces// part of the operand string delineated with iterators// with part of a parameter string delineated with iteratorsstring s7o("OOOOOOO");string s7p("PPPP");cout << "The operand string s7o is: " << s7o << endl;cout << "The parameter string s7p is: " << s7p << endl;basic_string<char>::iterator IterF3, IterL3, IterF4, IterL4;IterF3 = s7o.begin() + 1;IterL3 = s7o.begin() + 3;IterF4 = s7p.begin();IterL4 = s7p.begin() + 2;string result7a;result7a = s7o.replace(IterF3, IterL3, IterF4, IterL4);cout << "The result of s7o.replace (IterF3 ,IterL3 ,IterF4 ,IterL4)\n is "<< "the string: " << result7a << "." << endl;cout << endl;return;/*The parameter character c1p is: CThe result of s3o.replace(1, 3, 4, ch3p)is the string: ACCCCAAAA.The operand string s4o is: AAAAAAAAThe parameter string s4p is: BBBThe parameter C-string cs4p is: CCCThe result of s1o.replace (IterF0, IterL0, s4p)is the string: BBBAAAAA.The result of s4o.replace (IterF0, IterL0, cs4p)is the string: CCCAAAAA.The operand string s5o is: AAAAAAAFThe parameter C-string cs5p is: CCCBBThe result of s5o.replace (IterF1, IterL1, cs4p ,4)is the string: CCCBAAAF.The operand string s6o is: AAAAAAAGThe parameter character ch6p is: qThe result of s6o.replace (IterF1, IterL1, 4, ch6p)is the string: qqqqAAAAG.The operand string s7o is: OOOOOOOThe parameter string s7p is: PPPPThe result of s7o.replace (IterF3 ,IterL3 ,IterF4 ,IterL4)is the string: OPPOOOO.请按任意键继续. . .*/}//设置字符串与数的能力至少一样大指定数目void basic_string_reserve(void){using namespace std;string str1("Hello world");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type sizeStr1, sizerStr1;sizeStr1 = str1.size();basic_string <char>::size_type capStr1, caprStr1;capStr1 = str1.capacity();// Compare size & capacity of the original stringcout << "The current size of original string str1 is: "<< sizeStr1 << "." << endl;cout << "The capacity of original string str1 is: "<< capStr1 << "." << endl << endl;// Compare size & capacity of the string// with added capacitystr1.reserve(40);sizerStr1 = str1.size();caprStr1 = str1.capacity();cout << "The string str1with augmented capacity is: "<< str1 << endl;cout << "The current size of string str1 is: "<< sizerStr1 << "." << endl;cout << "The new capacity of string str1 is: "<< caprStr1 << "." << endl << endl;// Compare size & capacity of the string// with downsized capacitystr1.reserve();basic_string <char>::size_type sizedStr1;basic_string <char>::size_type capdStr1;sizedStr1 = str1.size();capdStr1 = str1.capacity();cout << "The string str1 with downsized capacity is: "<< str1 << endl;cout << "The current size of string str1 is: "<< sizedStr1 << "." << endl;cout << "The reduced capacity of string str1 is: "<< capdStr1 << "." << endl << endl;return;/*The original string str1 is: Hello worldThe current size of original string str1 is: 11.The capacity of original string str1 is: 15.The string str1with augmented capacity is: Hello worldThe current size of string str1 is: 11.The new capacity of string str1 is: 47.The string str1 with downsized capacity is: Hello worldThe current size of string str1 is: 11.The reduced capacity of string str1 is: 47.请按任意键继续. . .*/}//指定一个新的大小为一个字符串，添加或删除元素的要求void basic_string_resize(void){using namespace std;string  str1("Hello world");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type sizeStr1;sizeStr1 = str1.size();basic_string <char>::size_type capStr1;capStr1 = str1.capacity();// Compare size & capacity of the original stringcout << "The current size of original string str1 is: "<< sizeStr1 << "." << endl;cout << "The capacity of original string str1 is: "<< capStr1 << "." << endl << endl;// Use resize to increase size by 2 elements: exclamationsstr1.resize(str1.size() + 2, '!');cout << "The resized string str1 is: " << str1 << endl;sizeStr1 = str1.size();capStr1 = str1.capacity();// Compare size & capacity of a string after resizingcout << "The current size of resized string str1 is: "<< sizeStr1 << "." << endl;cout << "The capacity of resized string str1 is: "<< capStr1 << "." << endl << endl;// Use resize to increase size by 20 elements:str1.resize(str1.size() + 20);cout << "The resized string str1 is: " << str1 << endl;sizeStr1 = str1.size();capStr1 = str1.capacity();// Compare size & capacity of a string after resizing// note capacity increases automatically as requiredcout << "The current size of modified string str1 is: "<< sizeStr1 << "." << endl;cout << "The capacity of modified string str1 is: "<< capStr1 << "." << endl << endl;// Use resize to downsize by 28 elements:str1.resize(str1.size() - 28);cout << "The downsized string str1 is: " << str1 << endl;sizeStr1 = str1.size();capStr1 = str1.capacity();// Compare size & capacity of a string after downsizingcout << "The current size of downsized string str1 is: "<< sizeStr1 << "." << endl;cout << "The capacity of downsized string str1 is: "<< capStr1 << "." << endl;return;/*The original string str1 is: Hello worldThe current size of original string str1 is: 11.The capacity of original string str1 is: 15.The resized string str1 is: Hello world!!The current size of resized string str1 is: 13.The capacity of resized string str1 is: 15.The resized string str1 is: Hello world!!*/}//搜索在向后方向的字符串的子字符串的第一次出现的字符的指定序列相匹配void basic_string_rfind(void){using namespace std;// The first member function// searches for a single character in a stringstring str1("Hello Everyone");cout << "The original string str1 is: " << str1 << endl;basic_string <char>::size_type indexCh1a, indexCh1b;static const basic_string <char>::size_type npos = -1;indexCh1a = str1.rfind("e", 9);if (indexCh1a != npos)cout << "The index of the 1st 'e' found before the 9th"<< " position in str1 is: " << indexCh1a << endl;elsecout << "The character 'e' was not found in str1 ." << endl;indexCh1b = str1.rfind("x");if (indexCh1b != npos)cout << "The index of the 'x' found in str1 is: "<< indexCh1b << endl << endl;elsecout << "The character 'x' was not found in str1."<< endl << endl;// The second member function searches a string// for a substring as specified by a C-stringstring str2("Let me make this perfectly clear.");cout << "The original string str2 is: " << str2 << endl;basic_string <char>::size_type indexCh2a, indexCh2b;const char *cstr2 = "perfect";indexCh2a = str2.rfind(cstr2, 30);if (indexCh2a != npos)cout << "The index of the 1st element of 'perfect' "<< "before\n the 30th position in str2 is: "<< indexCh2a << endl;elsecout << "The substring 'perfect' was not found in str2 ."<< endl;const char *cstr2b = "imperfectly";indexCh2b = str2.rfind(cstr2b, 30);if (indexCh2b != npos)cout << "The index of the 1st element of 'imperfect' "<< "before\n the 5th position in str3 is: "<< indexCh2b << endl;elsecout << "The substring 'imperfect' was not found in str2 ."<< endl << endl;// The third member function searches a string// for a substring as specified by a C-stringstring str3("It is a nice day. I am happy.");cout << "The original string str3 is: " << str3 << endl;basic_string <char>::size_type indexCh3a, indexCh3b;const char *cstr3a = "nice";indexCh3a = str3.rfind(cstr3a);if (indexCh3a != npos)cout << "The index of the 1st element of 'nice' "<< "in str3 is: " << indexCh3a << endl;elsecout << "The substring 'nice' was not found in str3 ."<< endl;const char *cstr3b = "am";indexCh3b = str3.rfind(cstr3b, indexCh3a + 25, 2);if (indexCh3b != npos)cout << "The index of the next occurrance of 'am' in "<< "str3 begins at: " << indexCh3b << endl << endl;elsecout << "There is no next occurrence of 'am' in str3 ."<< endl << endl;// The fourth member function searches a string// for a substring as specified by a stringstring str4("This perfectly unclear.");cout << "The original string str4 is: " << str4 << endl;basic_string <char>::size_type indexCh4a, indexCh4b;string str4a("clear");indexCh4a = str4.rfind(str4a, 15);if (indexCh4a != npos)cout << "The index of the 1st element of 'clear' "<< "before\n the 15th position in str4 is: "<< indexCh4a << endl;elsecout << "The substring 'clear' was not found in str4 "<< "before the 15th position." << endl;string str4b("clear");indexCh4b = str4.rfind(str4b);if (indexCh4b != npos)cout << "The index of the 1st element of 'clear' "<< "in str4 is: "<< indexCh4b << endl;elsecout << "The substring 'clear' was not found in str4 ."<< endl << endl;return;/*The original string str1 is: Hello EveryoneThe index of the 1st 'e' found before the 9th position in str1 is: 8The character 'x' was not found in str1.The original string str2 is: Let me make this perfectly clear.The index of the 1st element of 'perfect' beforethe 30th position in str2 is: 17The substring 'imperfect' was not found in str2 .The original string str3 is: It is a nice day. I am happy.The index of the 1st element of 'nice' in str3 is: 8The index of the next occurrance of 'am' in str3 begins at: 20The original string str4 is: This perfectly unclear.The substring 'clear' was not found in str4 before the 15th position.The index of the 1st element of 'clear' in str4 is: 17请按任意键继续. . .*/}//返回字符串中的元素的当前数目void basic_string_size(void){using namespace std;string str1("Hello world");cout << "The original string str1 is: " << str1 << endl;// The size and length member functions differ in name onlybasic_string <char>::size_type sizeStr1, lenStr1;sizeStr1 = str1.size();lenStr1 = str1.length();basic_string <char>::size_type capStr1, max_sizeStr1;capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a stringcout << "The current size of original string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of original string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of original string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of original string str1 is: "<< max_sizeStr1 << "." << endl << endl;str1.erase(6, 5);cout << "The modified string str1 is: " << str1 << endl;sizeStr1 = str1.size();lenStr1 = str1.length();capStr1 = str1.capacity();max_sizeStr1 = str1.max_size();// Compare size, length, capacity & max_size of a string// after erasing part of the original stringcout << "The current size of modified string str1 is: "<< sizeStr1 << "." << endl;cout << "The current length of modified string str1 is: "<< lenStr1 << "." << endl;cout << "The capacity of modified string str1 is: "<< capStr1 << "." << endl;cout << "The max_size of modified string str1 is: "<< max_sizeStr1 << "." << endl;return;/*The original string str1 is: Hello worldThe current size of original string str1 is: 11.The current length of original string str1 is: 11.The capacity of original string str1 is: 15.The max_size of original string str1 is: 4294967294.The modified string str1 is: HelloThe current size of modified string str1 is: 6.The current length of modified string str1 is: 6.The capacity of modified string str1 is: 15.The max_size of modified string str1 is: 4294967294.请按任意键继续. . .*/}//副本最多某些字符数的一个字符串的子字符串从指定的位置开始void basic_string_substr(void){using namespace std;string  str1("Heterological paradoxes are persistent.");cout << "The original string str1 is: \n " << str1<< endl << endl;basic_string <char> str2 = str1.substr(6, 7);cout << "The substring str1 copied is: " << str2<< endl << endl;basic_string <char> str3 = str1.substr();cout << "The default substring str3 is: \n " << str3<< "\n which is the entire original string." << endl;return;/*The original string str1 is:Heterological paradoxes are persistent.The substring str1 copied is: logicalThe default substring str3 is:Heterological paradoxes are persistent.which is the entire original string.请按任意键继续. . .*/}//交换两个字符串的内容void basic_string_swap(void){using namespace std;// Declaring an objects of type basic_string<char>string s1("Tweedledee");string s2("Tweedledum");cout << "Before swapping string s1 and s2:" << endl;cout << " The basic_string s1 = " << s1 << "." << endl;cout << " The basic_string s2 = " << s2 << "." << endl;s1.swap(s2);cout << "After swapping string s1 and s2:" << endl;cout << " The basic_string s1 = " << s1 << "." << endl;cout << " The basic_string s2 = " << s2 << "." << endl;return;/*Before swapping string s1 and s2:The basic_string s1 = Tweedledee.The basic_string s2 = Tweedledum.After swapping string s1 and s2:The basic_string s1 = Tweedledum.The basic_string s2 = Tweedledee.请按任意键继续. . .*/}