c++从txt中读取数据，数据并不是一行路径，实用

#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

//but all of the whitespace that separated words (including newlines) was lost.

void ReadDataFromFileWBW()

{

ifstream fin("C:\\Users\\byte\\Desktop\\huang.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("C:\\Users\\byte\\Desktop\\huang.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("C:\\Users\\byte\\Desktop\\huang.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

getchar();

return 0;

}