System.DateTime.Now.ToString()的一些用法

    日期处理函数
    //2007年4月24日
    this.TextBox6.Text = System.DateTime.Now.ToString("D");
    //2007-4-24
    this.TextBox7.Text = System.DateTime.Now.ToString("d");

    //2007年4月24日 16:30:15
    this.TextBox8.Text = System.DateTime.Now.ToString("F");
    //2007年4月24日 16:30
    this.TextBox9.Text = System.DateTime.Now.ToString("f");

    //2007-4-24 16:30:15
    this.TextBox10.Text = System.DateTime.Now.ToString("G");
    //2007-4-24 16:30
    this.TextBox11.Text = System.DateTime.Now.ToString("g");

    //16:30:15
    this.TextBox12.Text = System.DateTime.Now.ToString("T");
    //16:30
    this.TextBox13.Text = System.DateTime.Now.ToString("t");

    //2007年4月24日 8:30:15
    this.TextBox14.Text = System.DateTime.Now.ToString("U");
    //2007-04-24 16:30:15Z
    this.TextBox15.Text = System.DateTime.Now.ToString("u");

    //4月24日
    this.TextBox16.Text = System.DateTime.Now.ToString("m");
    this.TextBox16.Text = System.DateTime.Now.ToString("M");
    //Tue, 24 Apr 2007 16:30:15 GMT
    this.TextBox17.Text = System.DateTime.Now.ToString("r");
    this.TextBox17.Text = System.DateTime.Now.ToString("R");
    //2007年4月
    this.TextBox19.Text = System.DateTime.Now.ToString("y");
    this.TextBox19.Text = System.DateTime.Now.ToString("Y");
    //2007-04-24T15:52:19.1562500+08:00
    this.TextBox20.Text = System.DateTime.Now.ToString("o");
    this.TextBox20.Text = System.DateTime.Now.ToString("O");
    //2007-04-24T16:30:15
    this.TextBox18.Text = System.DateTime.Now.ToString("s");
    //2007-04-24 15:52:19
    this.TextBox21.Text = System.DateTime.Now.ToString("yyyy-MM-ddHH：mm：ss：ffff");
    //2007年04月24 15时56分48秒
    this.TextBox22.Text = System.DateTime.Now.ToString("yyyy年MM月ddHH时mm分ss秒");

    //星期二, 四月 24 2007
    this.TextBox1.Text = System.DateTime.Now.ToString("dddd, MMMM ddyyyy");
    //二, 四月 24 '07
    this.TextBox2.Text = System.DateTime.Now.ToString("ddd, MMM d"'"yy");
    //星期二, 四月 24
    this.TextBox3.Text = System.DateTime.Now.ToString("dddd, MMMMdd");
    //4-07
    this.TextBox4.Text = System.DateTime.Now.ToString("M/yy");
    //24-04-07
    this.TextBox5.Text = System.DateTime.Now.ToString("dd-MM-yy");

DateTime.Now的后面有若干个ToString(),ToShortTimeString()之类的东东，到底都是干啥用的，还是做个程序测试一下吧

string str = "";

 str += "ToShortDateString:" + DateTime.Now.ToShortDateString() + " ";
 str += "ToShortTimeString:" + DateTime.Now.ToShortTimeString() + " ";
 str += "ToLongDateString" + DateTime.Now.ToLongDateString() + " ";
 str += "ToLongTimeString" + DateTime.Now.ToLongTimeString() + " ";
 str += "ToString:" + DateTime.Now.ToString() + " ";

 Response.Write( str );

运行结果是：

ToShortDateString:2006-2-13
ToShortTimeString:12:51
ToLongDateString:2006年2月13日
ToLongTimeString:12:51:17
ToString:2006-2-13 12:51:17

可以看出，要获得包含年月日时分秒的字符串，只要ToString()就可以

字符型转换转为字符串
   12345.ToString("n"); //生成 12,345.00
   12345.ToString("C"); //生成￥12,345.00
   12345.ToString("e"); //生成 1.234500e+004
   12345.ToString("f4"); //生成 12345.0000
   12345.ToString("x"); //生成 3039 (16进制)
   12345.ToString("p"); //生成 1,234,500