Java程序员学习C++之字符串

#include <iostream>#include <string.h>using namespace std;int my_len(const char *str){int len = 0;//while (*str != '\0')//{//++len;//++str;//}while (*(str++) != '\0'){++len;}return len;}void my_cpy(char *dst,const char *src){while (*src != '\0'){*dst = *src;++dst;++src;}}int main(){char str1[] = "abc";//后面自动加上'\0'char str2[] = { 'a', 'b', 'c' };//后面不会自动加上个'\0'，作为字符串会一直找到'\0'标志char str3[] = { 'a', 'b', 'c' ,'\0'};char str4[10] = "abc";//              4                      3                      4                      10cout << sizeof(str1) << "," << sizeof(str2) << "," << sizeof(str3) << "," << sizeof(str4) << endl;//              3                      15                      3                      3cout << strlen(str1) << "," << strlen(str2) << "," << strlen(str3) << "," << strlen(str4) << endl;cout << my_len(str1) << "," << my_len(str2) << "," << my_len(str3) << "," << my_len(str4) << endl;//       abc       abc烫烫烫烫蘟bc    abc            abccout << str1 << "," << str2 << "," << str3 << "," << str4 << endl;//字符串赋值//str1 = str2;// 错误，数组名是地址常量//str1 = "hello";// 错误，数组名是地址常量strcpy(str4,str1);//strcmp(str1,str2);字符串比较//strcat(str3,str2);字符串拼接，必须判断空间是否够//字符串分割char str[] = "this is a test";char *token = strtok(str, " ");while (token != NULL){cout << token << endl;token = strtok(NULL," ");}return 0;}

c++风格字符串

#include <iostream>#include <string>using namespace std;int main(){string str1 = "hello";string str2 = "abc";string str3 = "abc";//拷贝赋值str3 = str1;cout << str1 << "," << str3 << endl;//获取长度cout << str1.length() << endl;//字符串的比较str1.compare(str3);//字符串拼接str3 += str2;//字符串分割string str4 = "this is a test";//转换为c风格的string//char *token = strtok((char *)str4.c_str(), " ");//强制类型转换char *token = strtok(const_cast<char *>(str4.c_str()), " ");while (token != NULL){cout << token << endl;token = strtok(NULL, " ");}//遍历字符串(string::size_type i = 0; i < str1.length();i++)for (string::size_type i = 0; i < str1.length(); i++){cout << str1[i] << "-" ;}cout << endl;for (string::size_type i = 0; i < str1.length(); i++){cout << str1.at(i) << "-";}cout << endl;for (string::iterator itr = str1.begin(); itr != str1.end();++itr){cout << *itr << "-";}cout << endl;int cnt = 0;while (cnt < 50){if (str1.size() == str1.capacity()){//cout << "hhh";}str1.push_back('*');cnt++;//cout << str1.size() << "," << str1.capacity() << endl;}str1.clear();if (str1.empty()){cout << "str1.empty";}return 0;}