Url重写

1.定义url重写规则,很不幸的是一定要使用特定字符替代&,郁闷ing.........
<UrlReWriter enabled="true" reverse="true">
  <url pattern="/BBS/Forum/(d+).shtml" url="/BBS/Forum.aspx?BoardID=$1" repattern="/BBS/Forum.aspx?BoardID=(d+)$" reurl="/BBS/Forum/$1.shtml" />
  <url pattern="/BBS/Post/(d+).shtml" url="/BBS/Post.aspx?ArticleID=$1" repattern="/BBS/Post.aspx?ArticleID=(d+)$" reurl="/BBS/Post/$1.shtml"></url>
  <url pattern="/BBS/Forum/(d+)/(d+).shtml$" url="/BBS/Forum.aspx?BoardID=$1^type=$2" repattern="/BBS/Forum.aspx?BoardID=(d+)^type=(d+)$" reurl="/BBS/Forum/$1/$2.shtml" />
</UrlReWriter>

2.定义配置文件对应实体类

using System;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Xml;
using System.Web.Caching;

namespace DuwCompontents
...{
    /**//// <summary>
    /// url重写配置节实体类
    /// </summary>
    public class UrlReWriter
    ...{
        ...#region
        private string _Pattern;
        private string _Url;
        private string _RePattern;
        private string _ReUrl;
        #endregion

        ...#region

        /**//// <summary>
        /// 反向替换时url地址
        /// </summary>
        public string ReUrl
        ...{
            get ...{ return _ReUrl; }
        }

        /**//// <summary>
        /// 反向替换时正则
        /// </summary>
        public string Repattern
        ...{
            get ...{ return _RePattern; }
        }

        /**//// <summary>
        /// 真实url
        /// </summary>
        public string Url
        ...{
            get ...{ return _Url; }
        }

        /**//// <summary>
        /// 正则
        /// </summary>
        public string Pattern
        ...{
            get ...{ return _Pattern; }
        }
        #endregion

        构造#region 构造
        public UrlReWriter(XmlNode xn) ...{
            _Pattern = xn.Attributes["pattern"].Value;
            _Url = xn.Attributes["url"].Value;
            _RePattern = xn.Attributes["repattern"].Value;
            _ReUrl = xn.Attributes["reurl"].Value;
        }
        #endregion

    }
    /**//// <summary>
    /// url重写配置实体类
    /// </summary>
    public class UrlReWriterConfig
    ...{

        私有成员#region 私有成员
        private static string configFile = "/Configs/UrlReWriter.Config";
        
        private List<UrlReWriter> _UrlRewriter;
        private bool _Enabled;
        private bool _Reverse;
        
        #endregion

        公有属性#region 公有属性
        /**//// <summary>
        /// 反向匹配支持?
        /// </summary>
        public bool Reverse
        ...{
            get ...{ return _Reverse; }
        
        }
        /**//// <summary>
        /// 正向匹配支持?
        /// </summary>
        public bool Enabled
        ...{
            get ...{ return _Enabled; }
        }

        public List<UrlReWriter> UrlRewriters
        ...{
            get ...{ return _UrlRewriter; }
        }
        #endregion

        单件模式#region 单件模式
        private static UrlReWriterConfig _Config;
        
        static UrlReWriterConfig() ...{
            _Config = new UrlReWriterConfig();
            _Config._UrlRewriter = new List<UrlReWriter>();

            string file = HttpContext.Current.Server.MapPath( configFile );
            XmlDocument xd = new XmlDocument();
            xd.Load(file);
            XmlElement xe = xd.DocumentElement;
            bool enabled = true;
            if (xe.Attributes["enabled"] != null)
            ...{
                enabled = Boolean.TryParse(xe.Attributes["enabled"].Value, out enabled);
            }
            _Config._Enabled = enabled;

            bool reverse = true;
            if (xe.Attributes["reverse"] != null) ...{
                reverse = Boolean.TryParse(xe.Attributes["reverse"].Value, out reverse);
            }
            _Config._Reverse = reverse;
          
            foreach (XmlNode xn in xe.ChildNodes)
            ...{
                if (xn.NodeType == XmlNodeType.Element)
                ...{
                    UrlReWriter re = new UrlReWriter(xn);
                    _Config._UrlRewriter.Add(re);
                }
            }

        } 
        
        /**//// <summary>
        /// url重写配置实体类
        /// </summary>
        /// <returns></returns>
        public static UrlReWriterConfig Instance()
        ...{
            return _Config; 
        }
        #endregion
       
    }
}


3.实现IHttpModule(不使用ajax.net(atlas)可以不用处理AjaxPageFilter相关)
using System;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Web.Security;
using System.Xml;
using System.Text.RegularExpressions;

namespace DuwCompontents
...{
    public interface IRawPath
    ...{
        string GetPath();
    }
    public class DuwHttpModule : IHttpModule, IRawPath
    ...{

        IRawPath 成员#region IRawPath 成员
        //private string _rawPath = "";
        //public string GetPath()
        //{
        //   return _rawPath;
        //} 
        

        #endregion
        IHttpModule 成员#region IHttpModule 成员

        
        void IHttpModule.Dispose()
        ...{
            
        }

        void IHttpModule.Init(HttpApplication context)
        ...{
           
            context.BeginRequest += new EventHandler(context_BeginRequest);
            //context.ReleaseRequestState += new EventHandler(context_ReleaseRequestState);
        }

        
        #endregion

        事件#region 事件
        //void context_ReleaseRequestState(object sender, EventArgs e)
        //{
           // HttpResponse response = HttpContext.Current.Response;

           // if (response.ContentType == "text/plain")
           // {
           //     AjaxPageFilter filter = new AjaxPageFilter(response.Filter);
           //    response.Filter = filter;
           //     filter.RawPath = this;
           // }
        //}

 

        void context_BeginRequest(object sender, EventArgs e)
        ...{
            //这儿处理url重写
            string rawUrl = HttpContext.Current.Request.RawUrl;
            //_rawPath = rawUrl ;
            UrlReWriterConfig config = UrlReWriterConfig.Instance();
            if (HttpContext.Current.Request.Path.EndsWith(".shtml") && config.Enabled )
            ...{
                List<UrlReWriter> rewriters = UrlReWriterConfig.Instance().UrlRewriters;

                foreach (UrlReWriter rewriter in rewriters)
                ...{
                    string s_url = rewriter.Url.Replace("^", "&");
                   
                    Regex r = new Regex(rewriter.Pattern, RegexOptions.IgnoreCase);
                    if (r.IsMatch(rawUrl))
                    ...{
                        s_url = r.Replace(rawUrl, s_url); 
                        HttpContext.Current.RewritePath(s_url);
                        break;
                    }

                }
            }

        }
       
      
        #endregion

    }
}

4.配置IIS,主目录/配置,使用aspnet_isapi.dll处理.shtml.取消确认文件是否存在选择项

5,配置web.Config.支持自定义httpModule
<System.Web>
    <httpModules>
        <add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
        <!--type="完全限定名,程序集"-->
        <add name="DuwHttpModule" type="DuwCompontents.DuwHttpModule,DuwCompontents"/>
    </httpModules>
</System.Web>

6重写page类
using System;
using System.Collections.Generic;
using System.Text;
using System.Web.UI;
using System.Web.UI.WebControls;
using DuwCompontents;
using System.Text.RegularExpressions;
using System.IO;
using System.Web;

namespace DuwControls
...{
    public class DuwPage : Page
    ...{


       
        事件#region 事件
        protected override void Render(HtmlTextWriter writer)
        ...{
    //替换掉form action
            config = UrlReWriterConfig.Instance();
            if (config.Enabled) ...{
                if (writer is System.Web.UI.Html32TextWriter)
                ...{
                    writer = new FormFixerHtml32TextWriter(writer.InnerWriter);
                }
                else
                ...{
                    writer = new FormFixerHtmlTextWriter(writer.InnerWriter);
                }
            }
         //如果要求支持反向匹配
            if(config.Reverse)...{
                FindHyperLink(Controls);
            }

            base.Render(writer);
        }
        #endregion

        替换所有的服务端超链接#region 替换所有的服务端超链接
        private void FindHyperLink(ControlCollection controls) ...{
            foreach (Control ctrl in controls) ...{
                if (ctrl is HyperLink) ...{
                    ReplaceUrl(ctrl as HyperLink);
                }
                else if (ctrl is System.Web.UI.HtmlControls.HtmlAnchor) ...{
                    ReplaceUrl(ctrl as System.Web.UI.HtmlControls.HtmlAnchor);
                }
                else if (ctrl.Controls.Count > 0)
                ...{
                    FindHyperLink(ctrl.Controls);
                }
            }
        }
        private void ReplaceUrl(System.Web.UI.HtmlControls.HtmlAnchor hl)
        ...{
            UrlReWriterConfig config = UrlReWriterConfig.Instance();
            List<UrlReWriter> rewriters = UrlReWriterConfig.Instance().UrlRewriters;

            foreach (UrlReWriter rewriter in rewriters)
            ...{


                string s_url = rewriter.Repattern.Replace("^", "&");
                Regex r = new Regex(s_url, System.Text.RegularExpressions.RegexOptions.IgnoreCase);
                string rawUrl = hl.HRef;
                
                rawUrl = Regex.Replace(rawUrl, s_url, rewriter.ReUrl);
                if (hl.HRef != rawUrl)
                ...{
                    hl.HRef = rawUrl;
                    break;
                }
            
            }
        }
        private void ReplaceUrl(HyperLink hl) ...{
            UrlReWriterConfig config = UrlReWriterConfig.Instance();
            List<UrlReWriter> rewriters = UrlReWriterConfig.Instance().UrlRewriters;

            foreach (UrlReWriter rewriter in rewriters)
            ...{


                string s_url = rewriter.Repattern.Replace("^", "&");
                Regex r = new Regex(s_url, System.Text.RegularExpressions.RegexOptions.IgnoreCase);
                string rawUrl = hl.NavigateUrl;
                
                rawUrl = Regex.Replace(rawUrl, s_url, rewriter.ReUrl);
                if (hl.NavigateUrl != rawUrl)
                ...{
                    hl.NavigateUrl = rawUrl;
                    break;
                }
             

            }
        }
        #endregion

        替换掉Form的action#region 替换掉Form的action

        FormFixerHtml32TextWriter#region FormFixerHtml32TextWriter
        internal class FormFixerHtml32TextWriter : System.Web.UI.Html32TextWriter
        ...{
            private string _url; // 假的URL

            internal FormFixerHtml32TextWriter(TextWriter writer)
                : base(writer)
            ...{
                _url = HttpContext.Current.Request.RawUrl;
            }

            public override void WriteAttribute(string name, string value, bool encode)
            ...{
                // 如果当前输出的属性为form标记的action属性，则将其值替换为重写后的虚假URL
                if (_url != null && string.Compare(name, "action", true) == 0)
                ...{
                    value = _url;
                }
                base.WriteAttribute(name, value, encode);
            }
        }
        #endregion

        FormFixerHtmlTextWriter#region FormFixerHtmlTextWriter
        internal class FormFixerHtmlTextWriter : System.Web.UI.HtmlTextWriter
        ...{
            private string _url;
            internal FormFixerHtmlTextWriter(TextWriter writer)
                : base(writer)
            ...{
                _url = HttpContext.Current.Request.RawUrl;
            }

            public override void WriteAttribute(string name, string value, bool encode)
            ...{
                if (_url != null && string.Compare(name, "action", true) == 0)
                ...{
                    value = _url;
                }

                base.WriteAttribute(name, value, encode);
            }
        }
        #endregion

        #endregion
    }
}

7继续使用页面过滤器,使支持ajax.net(atlas)
using System;
using System.Text;
using System.Text.RegularExpressions;
using System.IO;
using System.Web;

namespace DuwCompontents
...{
    public class AjaxPageFilter : Stream
    ...{
        IRawPath _context = null;
        Stream responseStream;
        long position;
        StringBuilder responseHtml;

        public AjaxPageFilter(Stream inputStream)
        ...{
            responseStream = inputStream;
            responseHtml = new StringBuilder();
        }

        public override bool CanRead
        ...{
            get ...{ return true; }
        }

        public override bool CanSeek
        ...{
            get ...{ return true; }
        }

        public override bool CanWrite
        ...{
            get ...{ return true; }
        }

        public override void Close()
        ...{
            responseStream.Close();
        }

        public override void Flush()
        ...{
            responseStream.Flush();
        }

        public override long Length
        ...{
            get ...{ return 0; }
        }

        public override long Position
        ...{
            get ...{ return position; }
            set ...{ position = value; }
        }

        public override long Seek(long offset, SeekOrigin origin)
        ...{
            return responseStream.Seek(offset, origin);
        }

        public override void SetLength(long length)
        ...{
            responseStream.SetLength(length);
        }

        public override int Read(byte[] buffer, int offset, int count)
        ...{
            return responseStream.Read(buffer, offset, count);
        }

        public override void Write(byte[] buffer, int offset, int count)
        ...{
            string finalHtml = System.Text.UTF8Encoding.UTF8.GetString(buffer, offset, count);

            // Transform the response
            string formAction = RawPath.GetPath();
            if (!String.IsNullOrEmpty(formAction))
            ...{
                finalHtml = Regex.Replace(finalHtml, "\|\d+\|formAction\|\|[^\|]+\|",
                    "|" + formAction.Length.ToString() + "|formAction||" + formAction + "|",
                    RegexOptions.IgnoreCase);
            }

            // Write the response
            byte[] data = System.Text.UTF8Encoding.UTF8.GetBytes(finalHtml);
            responseStream.Write(data, 0, data.Length);
        }

        public IRawPath RawPath
        ...{
            get
            ...{
                return _context;
            }
            set
            ...{
                _context = value;

            }
        }
    }
}

8.取消3(DuwHttpModule)中的注释,转而支持AjaxPageFilter,
至此url重写工作完成,但是反向匹配虽然可以使我们几乎不用改任何一句代码
就支持全站的url重写,却是一个很浪费资源的行为,并不建议使用
http://blog.csdn.net/baozhenliang/archive/2007/04/30/1593280.aspx