JS中时间戳转日期格式（YYYY-MM-dd HH:mm:ss）

function formatUnixtimestamp (unixtimestamp){        var unixtimestamp = new Date(unixtimestamp*1000);        var year = 1900 + unixtimestamp.getYear();        var month = "0" + (unixtimestamp.getMonth() + 1);        var date = "0" + unixtimestamp.getDate();        var hour = "0" + unixtimestamp.getHours();        var minute = "0" + unixtimestamp.getMinutes();        var second = "0" + unixtimestamp.getSeconds();        return year + "-" + month.substring(month.length-2, month.length)  + "-" + date.substring(date.length-2, date.length)            + " " + hour.substring(hour.length-2, hour.length) + ":"            + minute.substring(minute.length-2, minute.length) + ":"            + second.substring(second.length-2, second.length); }