代码验证C#执行”文件打开关闭操作“耗时

2017-04-19

部门经理习惯用C#做数据清洗，遇到个需要验证的问题，在一个万次左右循环内对文件执行打开关闭操作，比在循环前打开文件、循环后关闭文件耗时多多少。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using System.Diagnostics;
using System.Threading;

namespace ConsoleApplication1
{
public class Program
{
static void Main(string[] args)
{
int index = 0;
long i = 0;
var stopWatch = new Stopwatch();
//StreamWriter f = new StreamWriter(@"D:\sum.txt", false);
for (i = 0; i < 100000; i++)
{
stopWatch.Start();
if (i == 10000)
{
stopWatch.Stop();
Console.WriteLine("Program run" + stopWatch.ElapsedMilliseconds + "ms.");
Thread.Sleep(10000);
}
i += 1;
Console.WriteLine(i);
StreamWriter f = new StreamWriter(@"D:\sum.txt", false);
index += 1;
f.Write(index);
f.Close();
}
//f.Close();
Console.ReadKey();
}
}
}