js获取当前时间日期，并将其格式化为YYYY-MM-DD，并且自定义返回

function(number = '', timer1 = 6) {
  if (!number) number = new Date();
  // var n = number * 1000
  var date = new Date(number);
  var Y = date.getFullYear();
  var M =
  (date.getMonth() + 1 < 10 ?
    "0" + (date.getMonth() + 1) :
    date.getMonth() + 1);
  var D = date.getDate() < 10 ? "0" + date.getDate() : date.getDate();
  var h = date.getHours() < 10 ? "0" + date.getHours() : date.getHours();
  var mm = date.getMinutes() < 10 ? "0" + date.getMinutes() : date.getMinutes();
  var s = date.getSeconds() < 10 ? "0" + date.getSeconds() : date.getSeconds();
  if (timer1 == 1) {
  return Y
  }
  if (timer1 == 2) {
  return Y + "-" + M
  }
  if (timer1 == 3) {
  return Y + "-" + M + "-" + D
  }
  if (timer1 == 4) {
  return Y + "-" + M + "-" + D + " " + h
  }
  if (timer1 == 5) {
  return Y + "-" + M + "-" + D + " " + h + ":" + mm
  }
  if (timer1 == 6) {
  return Y + "-" + M + "-" + D + " " + h + ":" + mm + ":" + s;
  }
}