C#返回指定目录最后写入时间

C#返回指定目录最后写入时间，主要用到了DirectoryInfo的LastWriteTime属性

using System;
using System.IO;
 
class MainClass {
    static void Main(string[] args) {
        FileInfo file = new FileInfo("c:\\a.txt");
 
        // Display directory information.
        DirectoryInfo dir = file.Directory;
 
        Console.WriteLine("Checking directory: " + dir.Name);
        Console.WriteLine("In directory: " + dir.Name);
        Console.Write("Directory exists: ");
        Console.WriteLine(dir.Exists.ToString());
 
        if (dir.Exists) {
            Console.Write("Directory last updated: ");
            Console.WriteLine(dir.LastWriteTime.ToString());
        }
        Console.WriteLine();
    }
}