学步园

统计代码文本文件的例子


代码来自：http://bbs.csdn.net/topics/390358144

错误代码：
#include <iostream>
 #include <fstream>
 #include <string>
 
int main()
 {
     using namespace std;
     const char filename[] = "test.cpp";
     ifstream fin;
     string temp;
 
    fin.open(filename);
     if (!fin.is_open())
     {
         cout << "不能打开文件"<< filename << endl;
         exit(EXIT_FAILURE);
     }
     int count = 0;
     getline(fin, temp);
     while (fin.good())
     {
         count++;
         getline(fin, temp);
     }
     fin.close();
     cout << "文件" << filename << "共有"
         << count << "行。\n";
     return 0;
 }
 
错误原因：getline遇到 eof， good函数返回false.所以没有计数，漏计了一行.


正确做法一:
int main()
{
	using namespace std;
	const char filename[] = "c:\\1.txt";
	ifstream fin;
	string temp;

	fin.open(filename);
	if (!fin.is_open())
	{
		cout << "不能打开文件"<< filename << endl;
		exit(EXIT_FAILURE);
	}
	int count = 0;
	

	while(fin.peek()!=EOF)
	{
		count++;
		getline(fin, temp);
		cout<<temp<<endl;
	}
	fin.close();
	cout << "文件" << filename << "共有"
		<< count << "行。\n";
	return 0;
}

注意不能用fin.eof ，会造成错误.


正确做法2：

#include <iostream>
#include <fstream>
#include <string>
using namespace std;

int main()
{
	using namespace std;
	const char filename[] = "test.txt";
	ifstream fin;
	string temp;

	fin.open(filename);
	if (!fin.is_open())
	{
		cout << "不能打开文件"<<filename << endl;
		exit(EXIT_FAILURE);
	}
	int count = 0;
	
	while (getline(fin, temp))
	{
		count++;
		cout<<temp<<endl;
	}
	fin.close();
	cout << "文件" << filename << "共有"
		<< count << "行。\n";

	getchar();
	return 0;
}