是否相同
这指示 Day.js 对象是否与其他提供的日期时间相同。
¥This indicates whether the Day.js object is the same as the other supplied date-time.
dayjs().isSame(dayjs('2011-01-01')) // default milliseconds
如果要将粒度限制为毫秒以外的单位，请将其作为第二个参数传递。
¥If you want to limit the granularity to a unit other than milliseconds, pass it as the second parameter.
当包含第二个参数时，它将匹配所有等于或大于的单位。传入 month 将检查 month 和 year。传入 day 将检查 day、month 和 year。
¥When including a second parameter, it will match all units equal or larger. Passing in month will check month and year. Passing in day will check day, month, and year.
dayjs().isSame('2011-01-01', 'year')
单位不区分大小写，并支持复数和缩写形式。
¥Units are case insensitive, and support plural and short forms.