转：Global.asax通过Application_BeginRequest()事件实现访问链接的静态地址映射

protected void Application_BeginRequest(Object sender, EventArgs e) {
        
        string strCurrentPath;
        strCurrentPath = Request.Path;
        //make sure that it ends with aspx.  This is some quick validation on the path. 
        //This will shortcut processing for images and other files (WebResource.axd, for example). 
        if(System.IO.Path.GetExtension(strCurrentPath).EndsWith(
            "aspx", true, System.Globalization.CultureInfo.InvariantCulture)) {
            string strCustomPath;
            string qString = Request.QueryString.ToString();
            if(qString != string.Empty)
                qString = "&" + qString;
            strCurrentPath = strCurrentPath.ToLowerInvariant();
            string appRoot = GetAppRoot(strCurrentPath);
            //string pageName = "";
            // the URL contains this folder name
            //Response.Write(strCurrentPath);
            if(strCurrentPath.IndexOf("catalog/", StringComparison.InvariantCultureIgnoreCase) > -1) {

                appRoot = appRoot.Replace("catalog/", "");
                strCustomPath = appRoot + "catalog.aspx?guid=" + System.IO.Path.GetFileNameWithoutExtension(strCurrentPath) + qString;

                // rewrite the URL
                Context.RewritePath(strCustomPath, false);
            }
            else if(strCurrentPath.IndexOf("product/", StringComparison.InvariantCultureIgnoreCase) > -1) {
                appRoot = appRoot.Replace("product/", "");

                strCustomPath = appRoot + "product.aspx?guid=" + System.IO.Path.GetFileNameWithoutExtension(strCurrentPath);
                // rewrite the URL

                Context.RewritePath(strCustomPath, false);
            }
        }
    }

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