c++中的输入详解

深藏阁楼爱情的钟 2021-09-28 01:58 300阅读 0赞

# 引言： #

>       在刷题过程中，字符串的输入是十分恶心人的，本文着重总结getline，cin.getline，scanf，cin的区别，是否读入空格，结束标识符。用string类型和char\[\]类型做测试

# 正文 #

> ## getline 读入字符串,cin.getline读入字符数组 ##
> 
> 用getline(cin，name)读入字符串，用cin.getline(place,256)读入字符数组
> 
> **总结：getline与cin.getline 2种都会 读入空格,并且以回车为结束标志符**

#include <iostream>
    
    #include <string>
    
    using namespace std;
    
    int main ()
    
    {
    
      string name;
    
      char place[256];
    
      //读入字符串
    
      cout << "Please, enter your full name: ";
    
      getline (cin,name);
    
      cout << "Hello, " << name << "!\n";
    
      cout<<endl<<endl;
    
      //读入数组
    
      cout << "Please, enter your full name: ";
    
      cin.getline(place,256);
    
      cout<<place<<" welcome you !"<<endl;
    
      return 0;
    
    }

> ## scanf与cin ##
> 
> 总结:scanf不能读入string类型，cin可以读入string与字符数组。并且scanf与cin都不读入空格,cin与scanf以空格作为判断符

#include <iostream>
    
    #include <string>
    
    using namespace std;
    
    int main ()
    
    {
    
      string name;
    
      char place[256];
    
      //读入字符串
    
      cout << "Please, enter your full name: ";
    
    //  scanf("%s",name);错误 不用用scanf读入字符串
    
      cout << "Hello, " << name << "!\n";
    
      cout<<endl<<endl;
    
      //读入数组
    
      cout << "Please, enter your full name: ";
    
    //  cin.getline(place,256);
    
            scanf("%s",place);
    
      cout<<place<<" welcome you !"<<endl;
    
      return 0;
    
    }

gets在c++14中已经被移除，并且容易出现bug，不推荐使用，所以此处讨论