• 操作符

  ==	// 關係操作符，從兩個字串的首字元根據字元的ASCII值開始比較
  >
  <
  >=
  <=
  !=
  + 	//s1 + s2,把 s1 和 s2 連線成一個新字串， 返回新生成的字串
  +=	// s1 += s2, 把 s2追加到s1中
  []	// str[n], 返回 str 中位置為 n 的字元，位置從 0 開始計數

• 舉例

#include <iostream>
#include <string>

using std::cout;
using std::endl;
using std::string;

int main(void)
{
        string str1("Hello, ");
        string str2 = "world!";

        string str3 = str1 + str2;

        string str4("Hello, world!");

        cout << "str1: " << str1 << endl;
        cout << "str5[1]: " << str5[1] << endl;
        if(str1 > str2)

        cout << "str2: " << str2 << endl;


        cout << "str3: " << str3 << endl;

        cout << "str4: " << str4 << endl;

        if(str3 == str4)
        {
                cout << "str3 == str4" << endl;
        }

        string str5(str1);
        str5 += str2;

        cout << "str5: " << str5 << endl;

        cout << "str5[1]: " << str5[1] << endl;
        
        if(str1 > str2)
        {
                cout << str1 << "大於" << str2 << endl;
        }
        else if(str1 == str2)
        {
                cout << str1 << "等於" << str2 << endl;
        }
        else
        {
                cout << str1 << "小於" << str2 << endl;
        }
        
        return 0;
}
 

PC:~/WorkSpace/CPP/string/3.2.3$ ./str_operators.exe 
str1: Hello, 
str2: world!
str3: Hello, world!
str4: Hello, world!
str3 == str4
str5: Hello, world!
str5[1]: e
Hello, 小於world!