Get Html Data Text After Open Printable Popup in c# Web Browser

I have a C# browser. Everything id Good . but i have problem When Open Many Website Popup Frame ...

i searched and find this Way :

Popup With c# Web Browser

this Code For popup Data Event

void w_NewWindow(string URL, int Flags, string TargetFrameName, ref object PostData, string Headers, ref bool Processed)
    {
        Processed = true;
        // SWEB = My Web Browser Form
        SWEB sw = new SWEB();
        if (URL.ToLower() != "about:blank")
        {
            sw.MYWEB.Navigate(URL);
        }
        else
        {

            // Document Write For Printable Data

            //   How Get Javascript Sended Data  ?
        }
        sw.Show();
    }

in the one Site : After Click For Print Button > Open Printable Page For Print Text, This Error is Showed.

Error > Page Url is : About:blank | Content is Clear

this Page is Blank(clear Page) but another Web Browser (firfox or IE OR ...) has Data(Html) Code For Print.

please help me for this . thanks