$(document).ready(function() {
    function cancelBackspace(e) {
        var retval = true;
        var elem = document.activeElement;
        if ( !$(elem).is("input:text") ) {
            if (e.keyCode == 8) {
                if (e.stopPropagation) {
                  e.stopPropagation();
                } else {
                  e.cancelBubble = true;
                }
                e.returnValue = false;
                e.originalEvent.returnValue = false;
                retval = false;
            }
        }
        return retval;
    }
    
    function cancelSubmitByEnter(e) {
        var retval = true;
        if (e.keyCode == 13) {
            retval = false;
        }
        return retval;
    }
    
    function cancelEvents(e) {
        var retval = true;
        
        retval = cancelBackspace(e);
        if (retval) {
            retval = cancelSubmitByEnter(e);
        }
        
        return retval;
    }
    
    $(document).keypress(function(e) {
        return cancelEvents(e);
    });
    $(document).keyup(function(e) {
        return cancelEvents(e);
    });
    $(document).keydown(function(e) {
        return cancelEvents(e);
    });
});