ui做自适应网站/搜索引擎推广的关键词

         JavaScript是一种基于对象和事件驱动并具有相对安全性的客户端脚本语言。同时也是一种广泛用于客户端Web开发的脚本语言，常用来给HTML网页添加动态功能，比如响应用户的各种操作。在牛腩新闻发布系统中有一下应用。

一、错误界面中的倒计时。

aspx文件的Javascript代码：

 <script language ="javascript" type ="text/javascript" >var i = 5;var intervalid;intervalid = setInterval("fun()", 1000);function fun() {if (i == 0) {window.location.href = "Default.aspx";clearInterval(intervalid);}document.getElementById("mes").innerHTML = i;i--;}
</script><p>将在<span id="mes">5</span>秒钟返回界面</p>

 

二、验证码。

先建立一个一般处理程序。代码如下：

<%@ WebHandler Language="C#" Class="WaterMark" %>using System;
using System.Web;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Web.SessionState;  public class WaterMark : IHttpHandler, IRequiresSessionState  // 要使用session必须实现该接口,记得要导入System.Web.SessionState命名空间
{public void ProcessRequest(HttpContext context){string checkCode = GenCode(5);  // 产生5位随机字符context.Session["Code"] = checkCode; //将字符串保存到Session中，以便需要时进行验证System.Drawing.Bitmap image = new System.Drawing.Bitmap(70, 22);Graphics g = Graphics.FromImage(image);try{//生成随机生成器Random random = new Random();//清空图片背景色g.Clear(Color.White);// 画图片的背景噪音线int i;for (i = 0; i < 25; i++){int x1 = random.Next(image.Width);int x2 = random.Next(image.Width);int y1 = random.Next(image.Height);int y2 = random.Next(image.Height);g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);}Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold));System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2F, true);g.DrawString(checkCode, font, brush, 2, 2);//画图片的前景噪音点g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);System.IO.MemoryStream ms = new System.IO.MemoryStream();image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);context.Response.ClearContent();context.Response.ContentType = "image/Gif";context.Response.BinaryWrite(ms.ToArray());}finally{g.Dispose();image.Dispose();}}/// <summary>/// 产生随机字符串/// </summary>/// <param name="num">随机出几个字符</param>/// <returns>随机出的字符串</returns>private string GenCode(int num){string str = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";char[] chastr = str.ToCharArray();// string[] source ={ "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "#", "$", "%", "&", "@" };string code = "";Random rd = new Random();int i;for (i = 0; i < num; i++){//code += source[rd.Next(0, source.Length)];code += str.Substring(rd.Next(0, str.Length), 1);}return code;}public bool IsReusable{get{return false;}}}

Aspx的代码：

开头有一段Javascript的代码：
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
<script language ="javascript" type ="text/javascript">function changeCode() {var imgNode = document.getElementById("vimg");imgNode.src = "WaterMark.ashx?t=" + (new Date()).valueOf(); // 这里加个时间的参数为了防止浏览器缓存的问题  }  
</script><p>验证码：<a name="com"> </a><img src="WaterMark.ashx" id="vimg" alt="" onclick ="changeCode()" /><asp:TextBox ID="txtCode" ValidationGroup ="pinglun"  runat="server" CssClass ="txtCode"></asp:TextBox><asp:RequiredFieldValidator ValidationGroup ="pinglun"  ID="RequiredFieldValidator1" runat="server"  ControlToValidate ="txtCode" ErrorMessage="请输入验证码"  Text ="*"></asp:RequiredFieldValidator><asp:Button ID="BtnSub" ValidationGroup ="pinglun" runat="server" Text="提交" οnclick="BtnSub_Click" /><asp:ValidationSummary ValidationGroup ="pinglun" ID="ValidationSummary1" runat="server" ShowMessageBox="true" ShowSummary ="false"   /></p>