Javascript : find first and last date of every month between two dates?

Question

我有两个日期，例如 1/04/2017 - 30/06/2017

我想找到上述日期范围内每个月的第一个和最后一个日期。

像这样-

1/04/2017 - 30/04/20171/05/2017 - 31/05/20171/06/2017 - 30/06/2017

这是因为我想在 fullcalendar 中使用这个解决方案来处理重复发生的事件，这样我就可以在下面的代码中添加日期范围 -

batches.push({
    id        : item.id,
    title     : item.title.textCapitalize(),
    start     : item.start_time,
    end       : item.end_time,
    dow       : item.weekdays,
    ranges    : 
    [
      {
        start   : '2017-04-01', //all of april
        end     : '2017-04-20',
      },
      {
        start   : '2017-05-01', //all of may
        end     : '2017-05-31',
      },
      {
        start   : '2017-06-01', //all of june
        end     : '2017-06-30',
      },
    ],
    backgroundColor : backgroundColor,
    borderColor     : backgroundColor
});

Answer 1

这是一个工作版本

const aDay = 24 * 60 * 60 * 1000;
const pad = num => ("0" + num).slice(-2);

const formatDate = d => d.getFullYear() + "-" + pad(d.getMonth() + 1) + "-" + pad(d.getDate());

const getRange = range => {
  ranges = [];

  console.log("start", range.start, "end", range.end)

  for (var i = range.start.getTime(), end = range.end.getTime(); i <= end;) {
    var first = new Date(i), last = new Date(first.getFullYear(), first.getMonth() + 1, 0); // last day of the month
    ranges.push({
      start: formatDate(first),
      end: formatDate(last)
    })
    i = last.getTime() + aDay;
    // if (!confirm(formatDate(new Date(i)))) break
  }
  return ranges;
}

let range = { // your range
  start: new Date(2019, 0, 1, 15, 0, 0, 0), // remember month is 0 based
  end: new Date(2020, 0, 1, 15, 0, 0, 0) // use 15:00 to help DST and Timzones yesterday
};
console.log(getRange(range))
range = { // your range
  start: new Date(2019, 1, 28, 15, 0, 0, 0), // remember month is 0 based
  end: new Date(2019, 4, 1, 15, 0, 0, 0) // use 15:00 to help DST and Timzones yesterday
};
console.log(getRange(range))