overrid events of Webbrowser ActiveX Control in .Net

      在.net中使用ie WebBrowser控件时，需要跟据自已的需求来定制组件的事件，风格等。其实在.net里控制ie组件的操作很简单，并且可以使用MSHTML提供的所有功能。您可以截获用户的所有操作事件，可以取得用户操作的对像以及对像的属性。下面是我的保留代码，以备后用。

    #region WebBrowser所需的事件触发定义
    /// 
    /// Generic HTML DOM Event method handler.
    /// 
    public delegate void DHTMLEvent(IHTMLEventObj e);
    /// 
    /// Generic Event handler for HTML DOM objects.
    /// Handles a basic event object which receives an IHTMLEventObj which
    /// applies to all document events raised.
    /// 
    public class DHTMLEventHandler
    {
        public DHTMLEvent Handler;
        HTMLDocument Document;
        public DHTMLEventHandler(HTMLDocument doc)
        {
            this.Document=doc;
        }
        [DispId(0)]
        public void Call()
        {
            Handler(Document.parentWindow.@event);
        }
    }
    #endregion

        private void axWebBrowserADS_DocumentComplete(object sender, AxSHDocVw.DWebBrowserEvents2_DocumentCompleteEvent e)
        {
            HTMLDocument doc = this.axWebBrowserADS.Document as HTMLDocument ;
            //绑定事件
            DHTMLEventHandler onclickHandler = new DHTMLEventHandler( doc ); 
            onclickHandler.Handler += new DHTMLEvent(this.myads_onclick);
            doc.onclick = onclickHandler;
        
            DHTMLEventHandler contextMenuHandler = new DHTMLEventHandler( doc ); 
            contextMenuHandler.Handler += new DHTMLEvent(this.myads_oncontextmenu);
            doc.oncontextmenu = contextMenuHandler;

            DHTMLEventHandler onkeydownHandler = new DHTMLEventHandler( doc ); 
            onkeydownHandler.Handler += new DHTMLEvent(this.myads_onkeydown);
            doc.onkeydown = onkeydownHandler;
            
            doc.body.style.border="none";
            doc.body.style.overflow="hidden";
        }

        private void myads_oncontextmenu(IHTMLEventObj pEvtObj)
        {
            pEvtObj.returnValue=false;
        }

        private void myads_onclick(IHTMLEventObj pEvtObj)
        {
            string a=pEvtObj.srcElement.GetType().ToString();
            if(a=="mshtml.HTMLAnchorElementClass")
            {
                mshtml.HTMLAnchorElementClass link=(mshtml.HTMLAnchorElementClass)pEvtObj.srcElement;
                if(link.href.Substring(0,5).ToUpper()=="JOIN:")
                {
                    clsVariable.FM_SERVICESLIST.doJOINcmd(link.href.Substring(5));
                    pEvtObj.returnValue=false;
                }
                else if(link.id.Substring(0,1)=="#")
                {
                    clsVariable.FM_SERVICESLIST.doJOINcmd(link.id);
                    pEvtObj.returnValue=false;
                }
                else
                {
                    link.target="_blank";
                }
            }
            else if(a=="mshtml.HTMLImgClass")
            {
                mshtml.HTMLImgClass img=(mshtml.HTMLImgClass)pEvtObj.srcElement;
                if(img.id!=null && img.id.Substring(0,1)=="#")
                {
                    clsVariable.FM_SERVICESLIST.doJOINcmd(img.id);
                    pEvtObj.returnValue=false;
                }
                else
                {
                    mshtml.HTMLAnchorElementClass link=(mshtml.HTMLAnchorElementClass)pEvtObj.srcElement;
                    if(link!=null)
                        link.target="_blank";
                }
            }
            else if(a=="mshtml.HTMLAreaElementClass")
            {
                mshtml.HTMLAreaElementClass area=(mshtml.HTMLAreaElementClass)pEvtObj.srcElement;
                if(area.href.Substring(0,5).ToUpper()=="JOIN:")
                {
                    clsVariable.FM_SERVICESLIST.doJOINcmd(area.href.Substring(5));
                    pEvtObj.returnValue=false;
                }
                else if(area.id!=null && area.id.Substring(0,1)=="#")
                {
                    clsVariable.FM_SERVICESLIST.doJOINcmd(area.id);
                    pEvtObj.returnValue=false;
                }
                else
                {
                    area.target="_blank";
                }
            }
        }

        private void myads_onkeydown(IHTMLEventObj pEvtObj)
        {
            if(pEvtObj.keyCode==8)    //backspace
            {
                pEvtObj.keyCode=0;
                pEvtObj.returnValue=false;
            }
            else if(pEvtObj.keyCode==116)    //KEY F5
            {
                pEvtObj.keyCode=0;
                pEvtObj.returnValue=false;
            }
            else if(pEvtObj.ctrlKey && pEvtObj.keyCode==70)    //Key ctrl+F
            {
                pEvtObj.keyCode=0;
                pEvtObj.returnValue=false;
            }
            else if(pEvtObj.ctrlKey && pEvtObj.keyCode==78)    //Key ctrl+N
            {
                pEvtObj.keyCode=0;
                pEvtObj.returnValue=false;
            }
            else if(pEvtObj.ctrlKey && pEvtObj.keyCode==80)    //Key ctrl+P
            {
                pEvtObj.keyCode=0;
                pEvtObj.returnValue=false;
            }
        }