【C++】string字符串查找替换、比较、提取、插入和删除

字符串的查找替换
字符串的比较
字符串的提取
字符串的插入和删除
Reference

字符串的查找替换

//c++string容器字符串查找替换
#include
#include
#include
using namespace std;

int main(){
    //int find(const string &str,int pos=0)const;
    //查找第一次出现的位置,从pos开始查找
    string str1 = "ehhe:haha:xixi:haha:heihei";
    string tmp = "haha";
    cout<<str1.find(tmp)<<endl;
    cout<<str1.find(tmp,10)<<endl;

    cout<<str1.find("haha")<<endl;

    //string& replace(int pos,int n,const string& str);
    //替换str第一次出现的位置,从pos开始查找
    str1.replace(5,4,"###");
    cout<<str1<<endl;

    string str2="www.17171272.sex.person.77.com";
    while(1){
        int ret = str2.find("sex");
        if(ret>str2.size()){
            cout<<"遍历查找完成"<<endl;
            break;
        }
        str2.replace(ret,strlen("sex"),"***");
    }
    cout<<str2<<endl;
    return 0;
}

5
15
5
ehhe:###:xixi:haha:heihei
遍历查找完成
www.17171272.***.person.77.com

字符串的比较

//c++string容器字符串的比较
#include
#include
using namespace std;
int main(){
    //compare函数在>时返回1, <是返回-1,等于时返回0
    string str1 = "hehe";
    string str2 = "haha";
    cout<<str1.compare(str1)<<endl;//1
    cout<<str1.compare("lala")<<endl;//-1
    cout<<str1.compare("hehe")<<endl;//0
    return 0;
}

字符串的提取

//c++string容器字符串的提取
#include
#include
using namespace std;
int main(){
    //string substr(int pos=0,int n=n)const;
    //返回由pos开始的n个字符组成的字符串
    string str1="hehehe:ha:xixixi:lalala:heihei";
    cout<<str1.substr(5,4)<<endl;

    int pos = 0;
    while(1){
        int ret = str1.find(":",pos);//从pos开始寻找":"
        if(ret<0){
            break;
        }
        string tmp =str1.substr(pos,ret-pos);
        cout<<tmp<<endl;
        pos=ret+1;
    }
    return 0;
}

e:ha
hehehe
ha
xixixi
lalala

字符串的插入和删除

//c++string容器字符串的插入和删除
#include
#include
using namespace std;
int main(){
    string str1="hello world";
    str1.insert(5,"hehe");
    cout<<str1<<endl;

    str1.erase(5,4);//删除hehe
    cout<<str1<<endl;

    //清空字符串
    str1.erase();
    cout<<str1.size()<<endl;   
    return 0;
}