DateTime.Now的一些用法

System.DateTime.Now.ToString("D");   //Tuesday, December 13, 2016

System.DateTime.Now.ToString("d");   //12/13/2016

System.DateTime.Now.ToString("F");   //Tuesday, December 13, 2016 4:53:52 PM

System.DateTime.Now.ToString("f");   //Tuesday, December 13, 2016 4:55 PM

System.DateTime.Now.ToString("G");

System.DateTime.Now.ToString();      // 12/13/2016 5:09:35 PM

System.DateTime.Now.ToString("g");   //12/13/2016 4:57 PM

System.DateTime.Now.ToString("T");   //4:57:56 PM

ystem.DateTime.Now.ToString("t");    //4:57PM

System.DateTime.Now.ToString("U");   //Tuesday, December 13, 2016 8:58:39 AM

System.DateTime.Now.ToString("u");   //2016-12-13 16:59:39Z

System.DateTime.Now.ToString("m");   //December 13
System.DateTime.Now.ToString("M");

System.DateTime.Now.ToString("r");    //Tue, 13 Dec 2016 17:01:20 GMT
System.DateTime.Now.ToString("R");

System.DateTime.Now.ToString("y");    //December, 2016
System.DateTime.Now.ToString("Y");

System.DateTime.Now.ToString("o");    //2016-12-13T17:02:24.1052667+08:00
System.DateTime.Now.ToString("O");

System.DateTime.Now.ToString("s");    //2016-12-13T17:02:59

System.DateTime.Now.ToString("yyyy-MM-dd  HH:mm:ss:ffff");  

//2016-12-13  17:03:59:4871

System.DateTime.Now.ToString("yyyy年MM月dd  HH时mm分ss秒");

// 2016年12月13  17时05分26秒