日期时间格式化(到毫秒)

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Threading;

public class MyClass
{
    public static void RunSnippet()
    {
        DateTime thisDate  = DateTime.Now;
        DateTime  utcDate  = thisDate.ToUniversalTime();
        //DateTime unspecifiedDate = new DateTime(2000, 3, 20, 13, 2, 3, 0, DateTimeKind.Unspecified);
        DateTime unspecifiedDate =  DateTime.Now;
        CultureInfo ci;
        string msgCulture  = "Culture:";
        string msgRoundtripUnspecified  = "(o) Roundtrip (Unspecified):. ";

        ci = Thread.CurrentThread.CurrentCulture;
        Console.WriteLine("{0,-30}{1}\n", msgCulture, ci.DisplayName);
        Console.WriteLine(msgRoundtripUnspecified +  unspecifiedDate.ToString("o", ci));
        String format="yyyyMMdd hh:mm:ss ffff"; 
        DateTime date=DateTime.Now; 
        Console.WriteLine(unspecifiedDate.ToString(format, DateTimeFormatInfo.InvariantInfo)); 
    }
    
    #region Helper methods
    
    public static void Main()
    {
        try
        {
            RunSnippet();
        }
        catch (Exception e)
        {
            string error = string.Format("---\nThe following error occurred while executing the snippet:\n{0}\n---", e.ToString());
            Console.WriteLine(error);
        }
        finally
        {
            Console.Write("Press any key to continue...");
            Console.ReadKey();
        }
    }

    private static void WL(object text, params object[] args)
    {
        Console.WriteLine(text.ToString(), args);    
    }
    
    private static void RL()
    {
        Console.ReadLine();    
    }
    
    private static void Break() 
    {
        System.Diagnostics.Debugger.Break();
    }

    #endregion
}