authcodehttphandler.cs

ASP.NET简洁论坛源代码 这是一个简单的论坛

using System;
using System.Web;
using System.Collections;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
using System.Drawing.Design;
using System.IO;
using System.Web.UI;
using System.Text;
using NetFocus.Web.Core;

namespace NetFocus.Web.Applications.Forum
{
    public class AuthCodeHttpHandler : IHttpHandler
    {
        int intLength = 4;               //长度
        string strIdentify = "AuthCode"; //随机字串存储键值，以便存储到Session中

        public void ProcessRequest(HttpContext context)
        {
            try
            {
                //设置输出流图片格式
                context.Response.ContentType = "image/gif";

                Bitmap b = new Bitmap(70, 19);
                Graphics g = Graphics.FromImage(b);
                g.FillRectangle(new SolidBrush(ColorTranslator.FromHtml("#EDF2F7")), 0, 0, 70, 19);
                Font font = new Font(FontFamily.GenericSerif, 16, FontStyle.Regular, GraphicsUnit.Pixel);
                Random r = new Random();

                //合法随机显示字符列表
                string strLetters = "1234567890";
                StringBuilder s = new StringBuilder();

                //将随机生成的字符串绘制到图片上
                for (int i = 0; i < intLength; i++)
                {
                    s.Append(strLetters.Substring(r.Next(0, strLetters.Length - 1), 1));
                    g.DrawString(s[s.Length - 1].ToString(), font, new SolidBrush(ColorTranslator.FromHtml("#2265b2")), 3 + i * 16, r.Next(0, 1));
                }

                b.Save(context.Response.OutputStream, ImageFormat.Gif);
                HttpCookie cookie = new HttpCookie(strIdentify, s.ToString());
                cookie.Expires = DateTime.Now.AddDays(1);
                context.Response.Cookies.Add(cookie);

                context.Response.End();

            }
            catch { }

        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }

    }
}