Script To Disable Ctrl Keys Combination

<script  language="JavaScript">


 function disableCtrlKeyCombination(e) {
        //list all CTRL + key combinations you want to disable
        var forbiddenKeys = new Array('a', 'n', 'c', 'x', 'v', 'j', 'w','p','u');
        var key;
        var isCtrl;
        if (window.event) {
            key = window.event.keyCode;     //IE
            if (window.event.ctrlKey)
                isCtrl = true;
            else
                isCtrl = false;
        }
        else {
            key = e.which;     //firefox
            if (e.ctrlKey)
                isCtrl = true;
            else
                isCtrl = false;
        }
        //if ctrl is pressed check if other key is in forbidenKeys array
        if (isCtrl) {
            for (i = 0; i < forbiddenKeys.length; i++) {
                //case-insensitive comparation
                if (forbiddenKeys[i].toLowerCase() == String.fromCharCode(key).toLowerCase()) {
                    //alert('Key combination CTRL + ' + String.fromCharCode(key) + ' has been disabled.');
                    return false;
                }
            }
        }
        return true;
    }
</script>