/// <summary>
        /// Begin Request
        /// </summary>
        /// <param name="sender">HttpApplication</param>
        /// <param name="e">Event Args.</param>
        public void context_BeginRequest(object sender, EventArgs e)
        {
            HttpApplication app = (HttpApplication)sender;
            String Prefix = "/";

            if (System.Web.Hosting.HostingEnvironment.ApplicationVirtualPath != "/")
            {
                Prefix = System.Web.Hosting.HostingEnvironment.ApplicationVirtualPath + "/";
            }
            Regex r1 = new Regex(Prefix + @"([0-9a-zA-Z\-]*)", RegexOptions.IgnoreCase);
            String Query = app.Request.Url.Query;
            if (Query.StartsWith("?"))
            {
                Query = "&" + Query.Substring(1, Query.Length - 1);
            }

            if (r1.Match(app.Request.Path).Success)
            {
                var agentno = DataAccess.Provider.SzAgentHelper.GetAgentNoByName(r1.Match(app.Request.Path).Groups[1].Value);
                if (agentno != null)
                    app.Context.RewritePath("~/blog/agent.aspx?id=E-" + agentno, false);
            }
}

 void Application_BeginRequest(Object sender, EventArgs e)
    {
        String oldUrl = System.Web.HttpContext.Current.Request.RawUrl;

        //其中()最为一个整体，.+任意多个除了（）以外的字符，^与字符串开始的地方匹配
        //d+任意多个数字，w+任意多个字母或数字或下划线
        String pattern = @"^(.+)/test4/(d+).aspx/(w+)";
        String replace = @"~/test4.aspx?NID=$1&id=$2&uid=$3";
        if(Regex.IsMatch(oldUrl,pattern,RegexOptions.IgnoreCase | RegexOptions.Compiled))
        {
            String newUrl=Regex.Replace(oldUrl,pattern,replace,RegexOptions.Compiled| RegexOptions.IgnoreCase);
            Context.RewritePath(newUrl);
        }
    }

------解决方案--------------------
伪静态