一.string类的构造函数

1.需要用到的头文件

#include<iostream>
#include<string>
using namespace std;

2. 函数实例

    string one("Lottery Winner!");           //直接将字符串赋值给string类
    cout << one << endl;                    //Lottery Winner!

    string two(20,'$');                     //输入字符个数和字符
    cout << two << endl;                    //$$$$$$$$$$$$$$$$$$$$

    string three(one);                      //初始化为string one
    cout << three << endl;                  //Lottery Winner!

    one += " oops!";                         //在string one后接字符串
    cout << one << endl;                    //Lottery Winner! oops!

    two = "Sorry ,That was ";               //为two重新赋值
    three[0]='P';                           //修改three[0]元素为 P
    string four;
    four = two + three;                     
    cout << four << endl;                   //Sorry ,That was Pottery Winner!

    char alls[]={"All's well that ends well"};
    string five(alls,20);                   //five初始化为alls的前20个字符
    cout << five << "!\n";                  //All's well that ends!

    string six(alls+6,alls+10);             //赋值为alls[6]到alls[9](数组名可看成指针)         
    cout << six << ', ';                    //well,

    string seven(&five[6],&five[10]);       //对象名不可看成指针
    cout << seven << "...\n";               //well...

    string eight(four,7,16);                //从four[7]开始,将16个字符复制到eight中
    cout << eight << "in motion!" << endl;  //That was Pottery in motion!

最终输出结果:

Lottery Winner!
$$$$$$$$$$$$$$$$$$$$
Lottery Winner!
Lottery Winner! oops!
Sorry! That was Pottery Winner!
All's well that ends!
well, well...
That was Pottery in motion!