SOURCE

function dateFormat(time) {
    var date = new Date(time);
    var year = date.getFullYear();
    var month = date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1) : date.getMonth() + 1;
    var day = date.getDate() < 10 ? "0" + date.getDate() : date.getDate();
    var hours = date.getHours() < 10 ? "0" + date.getHours() : date.getHours();
    var minutes = date.getMinutes() < 10 ? "0" + date.getMinutes() : date.getMinutes();
    var seconds = date.getSeconds() < 10 ? "0" + date.getSeconds() : date.getSeconds();
    // 拼接
    return year + "-" + month + "-" + day + " " + hours + ":" + minutes + ":" + seconds;
}

console.log(dateFormat(Date.now()))