C++中文件按行读取和逐词读取

2024-06-06 05:48

文章标签 c++ 读取按行逐词

本文主要是介绍C++中文件按行读取和逐词读取，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

#include  <iostream>
#include  <fstream>
#include  <string>using   namespace  std;void  OutPutAnEmptyLine()//输出空行
{
cout<< "\n" ;
}//读取方式: 逐词读取, 词之间用空格区分
void  ReadDataFromFileWBW()
{ 
cout<<"逐词读取, 词之间用空格区分"<<endl;
ifstream fin( "data.txt" );  
string  s;  
while ( fin >> s ) {
cout <<  "Read from file: "  << s << endl;  }
}//读取方式: 逐行读取, 将行读入字符数组, 行之间用回车换行区分
void  ReadDataFromFileLBLIntoCharArray()
{ 
cout<<"逐行读取, 将行读入字符数组, 行之间用回车换行区分"<<endl;
ifstream fin( "data.txt" ); 
const   int  LINE_LENGTH =  100 ; 
char  str[LINE_LENGTH];  
while ( fin.getline(str,LINE_LENGTH) )
{    
cout <<  "Read from file: "  << str << endl;
}
}//读取方式: 逐行读取, 将行读入字符串, 行之间用回车换行区分
//相比较上种方法，该种方法比较灵活，推荐使用
void  ReadDataFromFileLBLIntoString()
{
cout<<"逐行读取, 将行读入字符串, 行之间用回车换行区分"<<endl;
ifstream fin( "data.txt" );  
string  s;  
while ( getline(fin,s) )
{    
cout <<  "Read from file: "  << s << endl; 
}
}//带错误检测的读取方式
void  ReadDataWithErrChecking()
{string  filename =  "dataFUNNY.txt" ;  ifstream fin( filename.c_str());  if ( !fin ) {   
cout <<  "Error opening "  << filename <<  " for input"  << endl;   
exit(- 1 );  }
}int  main()
{
ReadDataFromFileWBW();  //逐词读入字符串 
OutPutAnEmptyLine();  //输出空行ReadDataFromFileLBLIntoCharArray();  //逐词读入字符数组
OutPutAnEmptyLine();  //输出空行ReadDataFromFileLBLIntoString();  //逐词读入字符串
OutPutAnEmptyLine();  //输出空行ReadDataWithErrChecking();  //带检测的读取
return   0 ;
}