如何使用moments.js和angularjs获取子午线(上午/下午) [英] How to get the meridian (am / pm) with momentsjs and angularjs

问题描述

我对库moments.js有疑问，我在angularjs中有一个应用程序，其中有六个选择元素，分别用于年，月，日，小时，分钟和am/pm格式.我正在使用以下格式来构建m.format日期('YYYY-MM-DD hh:mm:ss a).

I have a question about the library moments.js, I have an application in angularjs where I have six select elements for the year, month, day, hour, minutes, and am / pm format. I am using the following format moment to build m.format date ('YYYY-MM-DD hh: mm: ss a).

代码如下:

var m = moment([scope.val.year, scope.val.month, scope.val.date, scope.val.hour, scope.val.minute]); //build date 

model.$setViewValue(m.format('YYYY-MM-DD hh:mm:ss a'))

我得到了数据m.hour ()，m.minute ()等，但是有一种获取am/pm格式的方法，我没有找到任何有关它的信息，也许是m.meridian () => "am "or" pm ".

I get the data m.hour (), m.minute (), etc but there is a way to get the am / pm format, I have not found anything about it, something perhaps as m.meridian () => "am "or" pm ".

如果要创建一个数组作为参数，如果是am或pm，则可以从任何日期获取.

I would build the array passing as parameter if am or pm, and then also would get from any date if am or pm date.

推荐答案

几件事:

• 您要查找的单词是子午线" ，而不是子午线" .这是一个拉丁词，意为中午".是.是午后"(中午之前)​​和P.M.是午后"(中午之后).

• The word you're looking for is "meridiem", not "meridian". It's a Latin word meaning "mid-day". A.M. is "ante meridiem" (before mid-day) and P.M. is "post meridiem" (after mid-day).

.hours()函数和传递给moment构造函数的输入数组都期望24小时制的小时，从0到23.没有内置函数可以接受或输出12.小时时钟值或子午线(am/pm).

The .hours() function and the input array passed to the moment constructor both expect hours of a 24-hour clock, from 0 to 23. There is no built-in function to accept or output a 12-hour clock value, or a meridiem (am/pm).

目前的解析和格式化功能确实具有12小时时钟小时(h或hh)和子午线(A或a)的选项，但您没有解析或在您的用例中进行格式化，因此使用起来会有些笨拙.特别是，它们基于一刻的当前语言环境设置，因此，如果语言环境未固定为特定语言，则测试字符串将是有问题的.

The parsing and formatting functions in moment do have options for 12-hour clock hours (h or hh) and meridiem (A or a), but you're not parsing or formatting in your use case, so they would be a bit clumsy to use. In particular, they are based on moment's current locale settings, so testing a string would be problematic if the locale wasn't fixed to a specific language.

您可以使用这些简单的功能将12小时以上的子午后转换为24小时，反之亦然.它们不是特定于时刻的，因此您也可以将它们与Date对象或其他地方一起使用.

You can use these simple functions to convert from 12-hour + meridiem to 24-hour and vice-versa. They are not specific to moment, so you can also use them with the Date object or elsewhere.

function hours12to24(h, pm) {
    return h == 12 ? pm ? 12 : 0 : pm ? h + 12 : h;
}

function hours24to12(h) {
    return {
        hour : (h + 11) % 12 + 1,
        pm : h >= 12
    }
}

要测试这些功能，请执行以下操作:

To test these functions:

function test() {
  for (var i = 0; i <= 23; i++) {
    var x = hours24to12(i);
    var h = hours12to24(x.hour, x.pm);
    console.log(i + " == " + x.hour + (x.pm ? " pm" : " am") + " == " + h);
  }
}

此外，在调用.month()以获得月份数时要小心，结果为0-11，而不是1-12.构建输入数组时也是如此.您的下拉菜单需要使用0-11，或者需要相应地加减1.

Also, be careful when calling .month() to get the month number, the results are 0-11, not 1-12. The same is true when building the input array. Your dropdown either needs to use 0-11, or you need to add or subtract 1 accordingly.

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