moment().isSameOrBefore(Moment|String|Number|Date|Array);
moment().isSameOrBefore(Moment|String|Number|Date|Array, String);
检查一个 moment 是否在另一个 moment 之前或与之相同。 第一个参数会被解析为 moment（如果尚未解析）。
moment('2010-10-20').isSameOrBefore('2010-10-21'); // true
moment('2010-10-20').isSameOrBefore('2010-10-20'); // true
moment('2010-10-20').isSameOrBefore('2010-10-19'); // false
如果要将粒度限制为毫秒以外的单位，则将单位作为第二个参数传入。
由于第二个参数用于确定精度，且不仅仅是要检查的单个值，因此使用 day 将会检查年份、月份、日期。
moment('2010-10-20').isSameOrBefore('2009-12-31', 'year'); // false
moment('2010-10-20').isSameOrBefore('2010-12-31', 'year'); // true
moment('2010-10-20').isSameOrBefore('2011-01-01', 'year'); // true
与 moment#isAfter 和 moment#isSame 一样，moment#startOf 支持的任何时间单位也适用于 moment#isSameOrBefore：
year month week isoWeek day hour minute second
moment().isSameOrBefore(Moment|String|Number|Date|Array);
moment().isSameOrBefore(Moment|String|Number|Date|Array, String);
Check if a moment is before or the same as another moment. The first argument will be parsed as a moment, if not already so.
moment('2010-10-20').isSameOrBefore('2010-10-21'); // true
moment('2010-10-20').isSameOrBefore('2010-10-20'); // true
moment('2010-10-20').isSameOrBefore('2010-10-19'); // false
If you want to limit the granularity to a unit other than milliseconds, pass the units as the second parameter.
As the second parameter determines the precision, and not just a single value to check, using day will check for year, month and day.
moment('2010-10-20').isSameOrBefore('2009-12-31', 'year'); // false
moment('2010-10-20').isSameOrBefore('2010-12-31', 'year'); // true
moment('2010-10-20').isSameOrBefore('2011-01-01', 'year'); // true
Like moment#isAfter and moment#isSame, any of the units of time that are supported for moment#startOf are supported for moment#isSameOrBefore:
year month week isoWeek day hour minute second