ashx版本的验证码以及使用方法

 

代码如下：

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Drawing;
using System.Web.UI.WebControls;
using System.Web.SessionState;

namespace WebServiceClient2
{
    /// <summary>
    /// $codebehindclassname$ 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    public class CreatimageCode : IHttpHandler,IRequiresSessionState

    {
        System.IO.MemoryStream ms = new System.IO.MemoryStream();
        public void ProcessRequest(HttpContext context)
        {
            string checkCode = CreateCode(4);
            context.Session.Add("checkCode",(object)checkCode);
            CreateImage(checkCode);
            context.Response.ClearContent();
            context.Response.ContentType = "image/Gif";
            context.Response.BinaryWrite(ms.ToArray());
           
        }
        public string CreateCode(int codeLength)
        {

            string so = "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,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[] strArr = so.Split(',');
            string code = "";
            Random rand = new Random();
            for (int i = 0; i < codeLength; i++)
            {
                code += strArr[rand.Next(0,strArr.Length)];
            }
            return code;
        }

        /*产生验证图片*/
        public void CreateImage(string code)
        {

            Bitmap image = new Bitmap(60,20);
            Graphics g = Graphics.FromImage(image);
            WebColorConverter ww = new WebColorConverter();
            g.Clear((Color)ww.ConvertFromString("#FAE264"));

            Random random = new Random();
            //画图片的背景噪音线
            for (int i = 0; i < 12; 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.LightGray),x1,y1,x2,y2);
            }
            Font font = new Font("Arial",15,FontStyle.Bold | FontStyle.Italic);
            System.Drawing.drawing2d.LinearGradientBrush brush = new System.Drawing.drawing2d.LinearGradientBrush(
                new Rectangle(0,image.Width,image.Height),Color.Blue,Color.Gray,1.2f,true);
            g.DrawString(code,font,brush,0);

            //画图片的前景噪音点
            //for (int i = 0; i < 10; i++)
            //{
            //    int x = random.Next(image.Width);
            //    int y = random.Next(image.Height);
            //    image.SetPixel(x,Color.White);
            //}

            //画图片的边框线
            // g.DrawRectangle(new Pen(Color.Silver),image.Width - 1,image.Height - 1);
            image.Save(ms,System.Drawing.Imaging.ImageFormat.Gif);
            g.dispose();
            image.dispose();
        }
        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

在使用的时候只需要添加src即可，如下：

 

<img alt="" src="CreatimageCode.ashx" onclick="this.src='CreatimageCode.ashx?dd='+newGuid()" />//用ashx来产生验证码，这个用伪GUID来传参改变值
  <img alt="" src="ImageCode.aspx" onclick="this.src='CreatimageCode.ashx?dd='+new Date()" />//可以直接使用aspx页面，这个用时间传参来请求变换值

 

这个上面用到了一个伪GUID   方式如下：

 

<script type="text/javascript">

        function newGuid() {             var guid = "";             for (var i = 1; i <= 32; i++) {                 var n = Math.floor(Math.random() * 16.0).toString(16);                 guid += n;                 if ((i == 8) || (i == 12) || (i == 16) || (i == 20))                     guid += "-";             }             return guid;         }     </script>

接下来再去研究一下socket...