easyui 日期显示

{ field: 'UpdateDatetime', title: '更新时间', width: 100, align: 'left', sortable: true
, formatter: function (value, rec, index) {
var date = new Date(parseInt(value.replace(/\/Date\((-?\d+)\)\//, '$1')));
return(date.getFullYear() + "-" + date.getMonth() + "-" + date.getDate());
}
}