在网页中插入

//屏蔽网页右鍵,适用于IE6,IE7,IE8,FireFox,谷歌Chrome浏览器 开始
    function clickIE4() {
        if (event.button == 2) {
            return false;
        }
    }

    function clickNS4(e) {
        if (document.layers || document.getElementById && !document.all) {
            if (e.which == 2 || e.which == 3) {
                return false;
            }
        }
    }

    function OnDeny() {
        if (event.ctrlKey || event.keyCode == 78 && event.ctrlKey || event.altKey || event.altKey && event.keyCode == 115) {
            return false;
        }
    }

    if (document.layers) {
        document.captureEvents(Event.MOUSEDOWN);
        document.onmousedown = clickNS4;
        document.onkeydown = OnDeny();
    } else if (document.all && !document.getElementById) {
        document.onmousedown = clickIE4;
        document.onkeydown = OnDeny();
    }

    document.oncontextmenu = new Function("return false");
//屏蔽网页右鍵,适用于 IE6,IE7,IE8,FireFox,谷歌Chrome浏览器 结束

这段代码可以禁止了鼠标右键，可网页中有一段<p><iframe frameborder="0" scrolling="no" id="Iframe3" src="http://www.cuctv.com/default.aspx?tabid=629&amp;Ptype=beijinglxszy&amp;topicname=%E5%8C%97%E4%BA%AC%E7%95%99%E5%AD%A6%E7%94%9F%E4%B9%8B%E5%A4%9C" style="width: 684px; background: none repeat scroll 0% 0% rgb(255, 255, 255); height: 565px;"></iframe></p>iframe框架，这里面的内容却不能控制，该怎么写呀