30秒学会 JavaScript 片段 – formatDuration

Returns the human readable format of the given number of milliseconds.

Divide ms with the appropriate values to obtain the appropriate values for day, hour, minute, second and millisecond.
Use Object.entries() with Array.prototype.filter() to keep only non-zero values.
Use Array.prototype.map() to create the string for each value, pluralizing appropriately.
Use String.prototype.join(', ') to combine the values into a string.

代码片段

const formatDuration = ms => {
  if (ms < 0) ms = -ms;
  const time = {
    day: Math.floor(ms / 86400000),
    hour: Math.floor(ms / 3600000) % 24,
    minute: Math.floor(ms / 60000) % 60,
    second: Math.floor(ms / 1000) % 60,
    millisecond: Math.floor(ms) % 1000
  };
  return Object.entries(time)
    .filter(val => val[1] !== 0)
    .map(([key, val]) => `${val} ${key}${val !== 1 ? 's' : ''}`)
    .join(', ');
};

使用样例

formatDuration(1001); // '1 second, 1 millisecond'
formatDuration(34325055574); // '397 days, 6 hours, 44 minutes, 15 seconds, 574 milliseconds'