如何在Moment中枚举两个日期之间的日期 [英] How to enumerate dates between two dates in Moment

问题描述

我有两个时刻日期：

var fromDate = moment(new Date('1/1/2014'));
var toDate   = moment(new Date('6/1/2014'));

片刻是否提供了枚举这两个日期之间所有日期的方法？

Does moment provide a way to enumerate all of the dates between these two dates?

如果没有，除了制作一个循环，将 fromDate 增加1之前，还有更好的解决方案吗？到达 toDate ？

If not, is there any better solution other than to make a loop which increments the fromDate by 1 until it reaches the toDate?

编辑：添加日期枚举方法和问题

我已经嘲笑了一个枚举两个日期之间日期的方法，但我遇到了一个问题。

I've mocked up a method for enumerating the days between two dates, but I'm running into an issue.

  var enumerateDaysBetweenDates = function(startDate, endDate) {
    var dates = [];

    startDate = startDate.add(1, 'days');

    while(startDate.format('M/D/YYYY') !== endDate.format('M/D/YYYY')) {
      console.log(startDate.toDate());
      dates.push(startDate.toDate());
      startDate = startDate.add(1, 'days');
    }

    return dates;
  };

当我运行 enumerateDaysBetweenDates时，看看输出（时刻（新的日期） （'1/1/2014'）），时刻（新日期（'1/5/2014'））;

Thu Jan 02 2014 00:00:00 GMT-0800 (PST)
Fri Jan 03 2014 00:00:00 GMT-0800 (PST)
Sat Jan 04 2014 00:00:00 GMT-0800 (PST)
[ Sun Jan 05 2014 00:00:00 GMT-0800 (PST),
  Sun Jan 05 2014 00:00:00 GMT-0800 (PST),
  Sun Jan 05 2014 00:00:00 GMT-0800 (PST) ]

它是console.logging正确的日期，但只有最后的日期被添加到数组。这是怎么/为什么？这闻起来像某种变量引用问题 - 但我没有看到它。

It's console.logging the right dates, but only the final date is being added to the array. How/why is this? This smells like some sort of variable reference issue - but I'm not seeing it.

推荐答案

.add（） 是一种mutator方法，因此不必在此行中进行分配：

.add() is a mutator method, so the assignment in this line is unnecessary:

startDate = startDate.add(1, 'days');

你可以这样做，并产生同样的效果：

You can just do this, and have the same effect:

startDate.add(1, 'days');

虽然它的名字意味着创建一个新的 Date 对象， toDate（） 方法实际上只返回现有的内部日期对象。

While it's name would imply the creation of a new Date object, the toDate() method really just returns the existing internal Date object.

所以，没有您的方法调用正在创建新的日期或时刻对象实例。使用 .clone（） 获取新实例：

So, none of your method calls are creating new Date or moment object instances. Fix that by using .clone() to get a new instance:

startDate = startDate.clone().add(1, 'days');

或者更好的是，将值包装在时刻（） Mtz 在评论中建议，如果值是片刻，它将克隆实例对象，或者它将解析输入以创建新的时刻实例。

Or better yet, wrap the values in a call to moment() as Mtz suggests in a comment, and it will clone the instance, if the value is a moment object, or it will parse the input to create a new moment instance.

startDate = moment(startDate).add(1, 'days');

我认为日期枚举器方法不应该改变传入的任何参数。我会创建一个用于枚举的单独变量。我也直接比较日期，而不是比较字符串：

I think a date enumerator method should not change either of the arguments passed in. I'd create a separate variable for enumerating. I'd also compare the dates directly, rather than comparing strings:

var enumerateDaysBetweenDates = function(startDate, endDate) {
    var dates = [];

    var currDate = moment(startDate).startOf('day');
    var lastDate = moment(endDate).startOf('day');

    while(currDate.add(1, 'days').diff(lastDate) < 0) {
        console.log(currDate.toDate());
        dates.push(currDate.clone().toDate());
    }

    return dates;
};

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