【STL】C++ string 类基本用法样例

#define _CRT_SECURE_NO_DEPRECATE#include <string>    //  使用 string 类时须包含这个文件#include <iostream>using namespace std;int main(){string str1;//  输入与输出cout << "输入字符串 str1" << endl;cin >> str1; getchar();cout << str1 << endl << endl << endl;//  一行行读取 cout << "输入字符串 str1" << endl;getline( cin, str1 );cout << str1 << endl;//  与c字符转换string str2("Hello World!"), str3;char   str4[50];cout << "输入 C 字符串" << endl;scanf("%s", str4);str3= str4;cout << "str2 is " << str2 << endl;cout << "str3 is " << str3 << endl << endl << endl;//  求字符串的长度string str5;cout << "输入字符串 str5" << endl;cin >> str5;int   len= str5.size();cout << "字符串 str5的长度为" << len << endl << endl << endl;//  遍历字符串例子string str6;cout << "输入字符串 str6" << endl;cin >> str6;int i;for( i= 0; i< str6.size(); ++i )cout << str6[i];cout << endl << endl;//  比较两个字符串 比较规则同 c字符串比较规则string str7, str8;cout << "输入字符串 str7, str8 , 中间用空格格开" << endl;cin >> str7 >> str8;if( str7< str8 ) cout << str7 << "  小于 " << str8 << endl;else if( str7> str8 ) cout << str7 << "  大于 " << str8 << endl;else cout << str7 << "  等于 " << str8 << endl;//  字符串与字符相加 string str9= "Darren";char ch1= 'a', ch2= 'b';str9= str9+ ch1; cout << str9 << endl << endl;str9= ch2+ str9; cout << str9 << endl << endl << endl;//  字符串与字符串相加string str10= "Acm", str11= "ICPC";str10.append( str11 );cout << str10 << endl << endl;//  字符串是否包含子串  如果包含 则返回子串在目标串中第一次出现的位置 string str12= "I am a student", str13= "student", str14= "aaaaaaa";if( str12.find( str13 )!= -1 )  cout << "Find " << str13 << endl;if( str12.find( str14 )== -1 )  cout << "Not Find  " << str14 << endl;//  转换成 c_字符串string str15= "Hello World";printf("%s\n", str15.c_str() );system("pause"); return 0;}