// JScript File
 function getKeyCode(e)
    {
        if (window.event)
           return window.event.keyCode;
        else if (e)
           return e.which;
        else
           return null;
    }

    function keyRestrict(e, validchars) 
    {
        var key='', keychar='';
        key = getKeyCode(e);
        
        if (key == null) 
            return true;
            
        keychar = String.fromCharCode(key);
        keychar = keychar.toLowerCase();
        validchars = validchars.toLowerCase();
        
        if (validchars.indexOf(keychar) != -1)
            return true;
            
        if ( key==null || key==0 || key==8 || key==9 || key==13 || key==27 )
            return true;
            
        return false;
    }