C++语法小记---string类

string类

#include <iostream>
#include <string>

using namespace std;

// 实现字符串右移, 例子hello >> 2 ==> lohel
string operator >> (const string& str, int n)
{
    string ret = "";
    int pos = 0;
    
    n = n % str.length();
    pos = str.length() - n;
    ret = str.substr(pos);
    ret += str.substr(0, pos); //下标从0开始，包左不包右
    
    return ret;
}

int main()
{
    string str1 = "hello";
    string str2 = "world";
    
    // 1.获取字符串长度(不包括'')
    cout << "str1.length = " << str1.length() << endl;
    
    // 2.字符串接续
    cout << "str1 + str2 = " << str1 + str2 << endl;
    
    // 3.字符串遍历
    for(int i = 0; i < str1.length(); i++)
    {
        cout << str1[i] << " ";
    }
    cout <<endl;
    
    for(string::iterator it = str1.begin(); it != str1.end(); it++)
    {
        cout << *it << " ";
    }
    cout <<endl;
    
    // 4.string转化为C语言中的char*
    cout << "str1.c_str() = " << str1.c_str() <<endl;
    
    // 5.查找字符在字符串中的位置
    cout << "str1.find('o') = " << str1.find('o') <<endl;
    
    // 6.截取子串
    cout << "str1.substr(2) = " << str1.substr(2) <<endl;
    
    // 7.自己开发的接口
    cout << "str1 >> 2 = " << (str1 >> 2) <<endl;
    
    return 0;
}