您必须生成与此类似的javascript代码。。。

jQuery(function ($) {

    name = $(\'#name\').val();
    $(\'#name\').data(\'old_value\',name);

    window.onbeforeunload = function () {
        if ($(\'#name\').data(\'old_value\') !== $(\'#name\').val())
            return \'You have unsaved changes!\';
    }

});