JS屏蔽Flash右键菜单

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> 
<title>Yimin</title> 
<script type="text/javascript"> 
function NoRightClick(pid){ 
//pid:flash's parentNode id 
var el = document.getElementById(pid); 
if(el.addEventListener){ 
el.addEventListener("mousedown",function(event){ 
if(event.button == 2){ 
event.stopPropagation(); //for firefox 
event.preventDefault(); //for chrome 
} 
},true); 
}else{ 
el.attachEvent("onmousedown",function(){ 
if(event.button == 2){ 
el.setCapture(); 
} 
}); 
el.attachEvent("onmouseup",function(){ 
el.releaseCapture(); 
}); 
el.oncontextmenu = function(){ 
return false; 
}; 
} 
}
</script> 
</head> 
<body> 
<div id="testContent" style="800px"> 
<embed id="t1" height="780px" width="750" pluginspage="http://www.adobe.com/go/getflashplayer" wmode="opaque" menu="false" allowscriptaccess="sameDomain" algin="middle" name="t1" quality="high" bgcolor="#000000" style="" src="test.swf" type="application/x-shockwave-flash"/> 
</div> 
<script type="text/javascript"> 
var so = new SWFObject("test.swf", "t1", "800", "550", "9", "#000000"); 
so.addParam("quality", "high"); 
so.addParam("name", "t1"); 
so.addParam("id", "t1"); 
so.addParam("algin", "middle"); 
so.addParam("AllowScriptAccess", "sameDomain"); 
so.addParam("menu", "false"); 
so.addParam("wmode", "opaque"); 
so.addParam("pluginspage", "http://www.adobe.com/go/getflashplayer"); 
so.write("testContent"); 
NoRightClick("testContent"); 
</script> 
</body> 
</html>

winform代码中

 private void webView_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
        {
            //播放器Flash添加右键菜单
            HtmlElement bfq = webView.Document.GetElementById("CuPlayer");
            if (bfq!=null)
            {
                bfq.MouseDown += new HtmlElementEventHandler(bfq_MouseDown);
            }
        }

        void bfq_MouseDown(object sender, HtmlElementEventArgs e)
        {
            if (e.MouseButtonsPressed==MouseButtons.Right)
            {
                cmsControl.Show(e.MousePosition);//弹出右键菜单
                return;
            }
        }