当前文件： UrlReWriter/UrlRewriter/URLRewriter.Module.cs[5K，2009-6-12 11:57:50]，打开代码结构图

		            
  1using System;
  2using System.Web;
  3using System.Text.RegularExpressions;
  4using System.Configuration;
  5using URLRewriter.Config;
  6
  7namespace URLRewriter
  8...{
  9    public class RewriterModule : IHttpModule
 10    ...{
 11        public void Init(HttpApplication app)
 12        ...{
 13            // WARNING!  This does not work with Windows authentication!
 14            // If you are using Windows authentication, change to app.BeginRequest
 15            app.AuthorizeRequest += new EventHandler(this.URLRewriter);
 16        }
 17
 18        protected void URLRewriter(object sender, EventArgs e)
 19        ...{
 20            HttpApplication app = (HttpApplication) sender;
 21            string requestedPath = app.Request.Path;
 22        
 23            // get the configuration rules
 24            UrlsCollection rules = UrlsConfig.GetConfig().Urls;
 25
 26            for (int i = 0; i < rules.Count; i++)
 27            ...{
 28                // get the pattern to look for, and Resolve the Url (convert ~ into the appropriate directory)
 29                string lookFor = "^" + RewriterUtils.ResolveUrl(app.Context.Request.ApplicationPath, rules[i].VirtualUrl) + "$";
 30
 31                Regex re = new Regex(lookFor, RegexOptions.IgnoreCase);
 32                if (re.IsMatch(requestedPath))
 33                ...{
 34                    string sendToUrl = RewriterUtils.ResolveUrl(app.Context.Request.ApplicationPath, re.Replace(requestedPath, rules[i].DestinationUrl));
 35                    RewriterUtils.RewriteUrl(app.Context, sendToUrl);
 36                    break;
 37                }
 38            }
 39        
 40        }
 41
 42        public void Dispose() ...{ }
 43    }
 44
 45
 46
 47    /**//// <summary>
 48    /// Provides utility helper methods for the rewriting HttpModule and HttpHandler.
 49    /// </summary>
 50    /// <remarks>This class is marked as internal, meaning only classes in the same assembly will be
 51    /// able to access its methods.</remarks>
 52    internal class RewriterUtils
 53    ...{
 54        RewriteUrl#region RewriteUrl
 55        /**//// <summary>
 56        /// Rewrite's a URL using <b>HttpContext.RewriteUrl()</b>.
 57        /// </summary>
 58        /// <param name="context">The HttpContext object to rewrite the URL to.</param>
 59        /// <param name="sendToUrl">The URL to rewrite to.</param>
 60        internal static void RewriteUrl(HttpContext context, string sendToUrl)
 61        ...{
 62            string x, y;
 63            RewriteUrl(context, sendToUrl, out x, out y);
 64        }
 65
 66        /**//// <summary>
 67        /// Rewrite's a URL using <b>HttpContext.RewriteUrl()</b>.
 68        /// </summary>
 69        /// <param name="context">The HttpContext object to rewrite the URL to.</param>
 70        /// <param name="sendToUrl">The URL to rewrite to.</param>
 71        /// <param name="sendToUrlLessQString">Returns the value of sendToUrl stripped of the querystring.</param>
 72        /// <param name="filePath">Returns the physical file path to the requested page.</param>
 73        internal static void RewriteUrl(HttpContext context, string sendToUrl, out string sendToUrlLessQString, out string filePath)
 74        ...{
 75            // see if we need to add any extra querystring information
 76            if (context.Request.QueryString.Count > 0)
 77            ...{
 78                if (sendToUrl.IndexOf('?') != -1)
 79                    sendToUrl += "&" + context.Request.QueryString.ToString();
 80                else
 81                    sendToUrl += "?" + context.Request.QueryString.ToString();
 82            }
 83
 84            // first strip the querystring, if any
 85            string queryString = String.Empty;
 86            sendToUrlLessQString = sendToUrl;
 87            if (sendToUrl.IndexOf('?') > 0)
 88            ...{
 89                sendToUrlLessQString = sendToUrl.Substring(0, sendToUrl.IndexOf('?'));
 90                queryString = sendToUrl.Substring(sendToUrl.IndexOf('?') + 1);
 91            }
 92
 93            // grab the file's physical path
 94            filePath = string.Empty;
 95            filePath = context.Server.MapPath(sendToUrlLessQString);
 96
 97            // rewrite the path...
 98            context.RewritePath(sendToUrlLessQString, String.Empty, queryString);
 99        }
100        #endregion
101
102        /**//// <summary>
103        /// Converts a URL into one that is usable on the requesting client.
104        /// </summary>
105        /// <remarks>Converts ~ to the requesting application path.  Mimics the behavior of the 
106        /// <b>Control.ResolveUrl()</b> method, which is often used by control developers.</remarks>
107        /// <param name="appPath">The application path.</param>
108        /// <param name="url">The URL, which might contain ~.</param>
109        /// <returns>A resolved URL.  If the input parameter <b>url</b> contains ~, it is replaced with the
110        /// value of the <b>appPath</b> parameter.</returns>
111        internal static string ResolveUrl(string appPath, string url)
112        ...{
113            if (url.Length == 0 || url[0] != '~')
114                return url;        // there is no ~ in the first character position, just return the url
115            else
116            ...{
117                if (url.Length == 1)
118                    return appPath;  // there is just the ~ in the URL, return the appPath
119                if (url[1] == '/' || url[1] == '\\')
120                ...{
121                    // url looks like ~/ or ~\
122                    if (appPath.Length > 1)
123                        return appPath + "/" + url.Substring(2);
124                    else
125                        return "/" + url.Substring(2);
126                }
127                else
128                ...{
129                    // url looks like ~something
130                    if (appPath.Length > 1)
131                        return appPath + "/" + url.Substring(1);
132                    else
133                        return appPath + url.Substring(1);
134                }
135            }
136        }
137    }
138
139}
140