C# txt格式记录时间，时间对比，决定是否更新代码记录Demo

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace fileIO
{
class Program
{
static void Main(string[] args)
{
string filename =AppDomain.CurrentDomain.BaseDirectory+ "companyUpdateLog.txt";
if (File.Exists(filename))
{
string time=ReadLog(filename);
if (time != "") {
DateTime dt;
if (DateTime.TryParse(time, out dt)) {
DateTime dtnow = DateTime.Now;
int days = (dtnow - dt).Days;
if (days == 7)
{
//开始更新
Console.WriteLine("正在更新");
WriteLog(filename, dtnow.ToString("yyyy-MM-dd HH:mm:ss"));
}
else {
Console.WriteLine("无需更新");
}
}
}
}
else {
DateTime dtnow = DateTime.Now;
//开始更新
Console.WriteLine("文件不存在时候：正在更新");
WriteLog(filename, dtnow.ToString("yyyy-MM-dd HH:mm:ss"));
}

Console.ReadLine();
}

public static  void WriteLog(string path,string text) {
using (FileStream file = new FileStream(path, FileMode.OpenOrCreate))
{
StreamWriter sw = new StreamWriter(file);
sw.Write(text);
sw.Close();
}
}
public static string ReadLog(string path)
{
string a="";
using (FileStream file = new FileStream(path, FileMode.Open))
{
StreamReader sw = new StreamReader(file);
a=sw.ReadToEnd();
sw.Close();
}
return a;
}