菜鸟问一个关于ifstream 读文件的问题
问题是这样的，我现在读取txt文件出了问题
为了测试这个问题，我在网上copy了一段代码
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
//输出空行
void OutPutAnEmptyLine()
{
cout<<"\n";
}
//读取方式: 逐词读取, 词之间用空格区分
//read data from the file, Word By Word
//when used in this manner, we'll get space-delimited bits of text from the file
/t all of the whitespace that separated words (including newlines) was lost.
void ReadDataFromFileWBW()
{
ifstream fin("E:\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
//If we were interested in preserving whitespace,
//we could read the file in Line-By-Line using the I/O getline() function.
void ReadDataFromFileLBLIntoCharArray()
{
ifstream fin("E:\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
//If you want to avoid reading into character arrays,
//you can use the C++ string getline() function to read lines into strings
void ReadDataFromFileLBLIntoString()
{
ifstream fin("E:\data.txt");
string s;
while( getline(fin,s) )
{
cout << "Read from file: " << s << endl;
}
}
//带错误检测的读取方式
//Simply evaluating an I/O object in a boolean context will return false
//if any errors have occurred
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;
}
// 输出结果为:
// Read from file: Fry:
// Read from file: One
// Read from file: Jillion
// Read from file: dollars.
// Read from file: [Everyone
// Read from file: gasps.]
// Read from file: Auctioneer:
// Read from file: Sir,
// Read from file: that's
// Read from file: not
// Read from file: a
// Read from file: number.
// Read from file: 数据读取，
// Read from file: 测试
// Read from file: 。
//
// Read from file: Fry: One Jillion dollars.
// Read from file: [Everyone gasps.]
// Read from file: Auctioneer: Sir, that's not a number.
// Read from file: 数据读取， 测试 。
//
// Read from file: Fry: One Jillion dollars.
// Read from file: [Everyone gasps.]
// Read from file: Auctioneer: Sir, that's not a number.
// Read from file: 数据读取， 测试 。
//
// Error opening dataFUNNY.txt for input
// Press any key to continue
然后我在E盘新建了一个data.txt文件，内容跟上面一样
可是出来的结果直接跳到了错误检测函数
如果把这个错误检测函数屏蔽掉，就是press any key to continue，这就跟我现在正急着做的那个程序读出来的结果是一样的
