屏蔽web页面的右键，但不屏蔽输入框中的右键

        if (document.layers) {
            document.captureEvents(Event.MOUSEDOWN);
        }
        document.onmousedown = click;
        document.oncontextmenu = new Function("return false;")

        function click(e) {
            e = e || event;
            if (e.button == 2) {
                var tag = e.srcElement || e.target;
                if (tag.type == "text" || tag.type == "textarea") {
                    document.oncontextmenu = new Function("return true;")
                }
                else {
                     
                    document.oncontextmenu = new Function("return false;")
                }
            }

        }

相关连接：http://www.din.or.jp/~hagi3/JavaScript/JSTips/Mozilla/Samples/MouseEvent.htm