private void InjectAlertBlocker()
        {
            HtmlElement head = wbNav.Document.GetElementsByTagName("head")[0];
            HtmlElement scriptEl = wbNav.Document.CreateElement("script");
            mshtml.IHTMLScriptElement element = (mshtml.IHTMLScriptElement)scriptEl.DomElement;
            string alertBlocker = "window.alert = function () { }";
            element.text = alertBlocker;
            head.AppendChild(scriptEl);
            wbNav.ScriptErrorsSuppressed = true;
        }

//阻止弹出新窗口
        private void wbNav_NewWindow(object sender, CancelEventArgs e)
        {
            e.Cancel = true;
        }
　　　　//必须要在这个事件里面调用才能禁用，之前一直写在别的事件里面，浪费了2小时。
        private void wbNav_Navigated(object sender, WebBrowserNavigatedEventArgs e)
        {
            InjectAlertBlocker();
        }