js格式化日期

//格式化时间 (1) yyyy-MM-dd hh:mm:ss
function formatTime(date, t) {
  var year = date.getFullYear();
  var month = date.getMonth() + 1;
  var day = date.getDate();
  var hour = date.getHours();
  var minute = date.getMinutes();
  var second = date.getSeconds();
  if (t === 'h:m') { return [hour, minute].map(formatNumber).join(':'); }
  else { return [year, month, day].map(formatNumber).join('-') + ' ' + [hour, minute, second].map(formatNumber).join(':'); }
}

//格式化时间 (2) yyyy-MM-dd
function currentTime(date, t) {
  var year = date.getFullYear();
  var month = date.getMonth() + 1;
  var day = date.getDate();
  // var hour = date.getHours();
  // var minute = date.getMinutes();
  // var second = date.getSeconds();
  if (t === 'h:m') { return [hour, minute].map(formatNumber).join(':'); }
  else { return [year, month, day].map(formatNumber).join('-'); }
}

//格式化时间（3）js转时间为昨天 今天 刚刚 
function timestampFormat(dateStr) {
  function zeroize(num) {
    return (String(num).length == 1 ? '0' : '') + num;
  }
  var timestamp = dateStr / 1000;
  var curTimestamp = parseInt(new Date().getTime() / 1000); //当前时间戳
  var timestampDiff = curTimestamp - timestamp; // 参数时间戳与当前时间戳相差秒数
  var curDate = new Date(curTimestamp * 1000); // 当前时间日期对象
  var tmDate = new Date(timestamp * 1000); // 参数时间戳转换成的日期对象

  var Y = tmDate.getFullYear(),
    m = tmDate.getMonth() + 1,
    d = tmDate.getDate();
  var H = tmDate.getHours(),
    i = tmDate.getMinutes(),
    s = tmDate.getSeconds();
  if (timestampDiff < 60) { // 一分钟以内
    return "刚刚";
  } else if (timestampDiff < 3600) { // 一小时前之内
    return Math.floor(timestampDiff / 60) + "分钟前";
  } else if (curDate.getFullYear() == Y && curDate.getMonth() + 1 == m && curDate.getDate() == d) {
    return '今天' + zeroize(H) + ':' + zeroize(i);
  } else {
    var newDate = new Date((curTimestamp - 86400) * 1000); // 参数中的时间戳加一天转换成的日期对象
    if (newDate.getFullYear() == Y && newDate.getMonth() + 1 == m && newDate.getDate() == d) {
      return '昨天' + zeroize(H) + ':' + zeroize(i);
    } else if (curDate.getFullYear() == Y) {
      return zeroize(m) + '月' + zeroize(d) + '日 ' + zeroize(H) + ':' + zeroize(i);
    } else {
      return Y + '年' + zeroize(m) + '月' + zeroize(d) + '日 ' + zeroize(H) + ':' + zeroize(i);
    }
  }
}

//js获取n天之前或n天之后的日期
function fun_date(now,n) {
  var date = new Date(now);
  date.setDate(date.getDate() + n);
  return date.getFullYear() + "-" + (date.getMonth() + 1) + "-" + date.getDate();
}