js日期转换工具

//进行日期转换
 function formatDate(now) {
        debugger
        var year = now.getFullYear();
        var month = now.getMonth() + 1;
        var date = now.getDate()-10;
        var hour = now.getHours();
        var minute = now.getMinutes();
        var second = now.getSeconds();
        return year + "-" + month + "-" + date;
    }