因为做fiddler抓包时出现了tunnel to的情况，所以修改了OnBeforeRequest的代码，以下内容是fiddler原来的OnBeforeRequest方法

 static function OnBeforeRequest(oSession: Session) {
        // Sample Rule: Color ASPX requests in RED
        // if (oSession.uriContains(".aspx")) { oSession["ui-color"] = "red";   }

        // Sample Rule: Flag POSTs to fiddler2.com in italics
        // if (oSession.HostnameIs("www.fiddler2.com") && oSession.HTTPMethodIs("POST")) {  oSession["ui-italic"] = "yup";  }

        // Sample Rule: Break requests for URLs containing "/sandbox/"
        // if (oSession.uriContains("/sandbox/")) {
        //     oSession.oFlags["x-breakrequest"] = "yup";   // Existence of the x-breakrequest flag creates a breakpoint; the "yup" value is unimportant.
        // }

        if ((null != gs_ReplaceToken) && (oSession.url.indexOf(gs_ReplaceToken)>-1)) {   // Case sensitive
            oSession.url = oSession.url.Replace(gs_ReplaceToken, gs_ReplaceTokenWith); 
        }
        if ((null != gs_OverridenHost) && (oSession.host.toLowerCase() == gs_OverridenHost)) {
            oSession["x-overridehost"] = gs_OverrideHostWith; 
        }

        if ((null!=bpRequestURI) && oSession.uriContains(bpRequestURI)) {
            oSession["x-breakrequest"]="uri";
        }

        if ((null!=bpMethod) && (oSession.HTTPMethodIs(bpMethod))) {
            oSession["x-breakrequest"]="method";
        }

        if ((null!=uiBoldURI) && oSession.uriContains(uiBoldURI)) {
            oSession["ui-bold"]="QuickExec";
        }

        if (m_SimulateModem) {
            // Delay sends by 300ms per KB uploaded.
            oSession["request-trickle-delay"] = "300"; 
            // Delay receives by 150ms per KB downloaded.
            oSession["response-trickle-delay"] = "150"; 
        }

        if (m_DisableCaching) {
            oSession.oRequest.headers.Remove("If-None-Match");
            oSession.oRequest.headers.Remove("If-Modified-Since");
            oSession.oRequest["Pragma"] = "no-cache";
        }

        // User-Agent Overrides
        if (null != sUA) {
            oSession.oRequest["User-Agent"] = sUA; 
        }

        if (m_Japanese) {
            oSession.oRequest["Accept-Language"] = "ja";
        }

        if (m_AutoAuth) {
            // Automatically respond to any authentication challenges using the 
            // current Fiddler user's credentials. You can change (default)
            // to a domain\\username:password string if preferred.
            //
            // WARNING: This setting poses a security risk if remote 
            // connections are permitted!
            oSession["X-AutoAuth"] = "(default)";
        }

        if (m_AlwaysFresh && (oSession.oRequest.headers.Exists("If-Modified-Since") || oSession.oRequest.headers.Exists("If-None-Match")))
        {
            oSession.utilCreateResponseAndBypassServer();
            oSession.responseCode = 304;
            oSession["ui-backcolor"] = "Lavender";
        }
    }