date-util

官网： https://www.npmjs.com/package/date-util
日期格式：

• d: Day of the month without leading zeros
• dd: Day of the month, 2 digits with leading zeros
• ddd: A textual representation of a day, three letters
• dddd: A full textual representation of the day of the week
• m: Numeric representation of a month, without leading zeros
• mm: Numeric representation of a month, with leading zeros
• mmm: A short textual representation of a month, three letters
• mmmm: A full textual representation of a month, such as January or March
• yy: A two digit representation of a year
• yyyy: A full numeric representation of a year, 4 digits
• h: 12-hour format of an hour without leading zeros
• hh: 12-hour format of an hour with leading zeros
• H: 12-hour format of an hour without leading zeros
• HH: 24-hour format of an hour with leading zeros
• M: Minutes without leading zeros
• MM: Minutes with leading zeros
• s: Seconds, without leading zeros
• ss: Seconds, with leading zeros
• l: Milliseconds, 3 digits
• L: Milliseconds without leading zeros
• t: Lowercase Ante meridiem and Post meridiem, 1 digit
• tt: Lowercase Ante meridiem and Post meridiem, 2 digits
• T: Uppercase Ante meridiem and Post meridiem, 1 digit
• TT: Uppercase Ante meridiem and Post meridiem, 2 digits
• Z: Difference to Greenwich time (GMT) in hours, with "GMT" word
• o: Difference to Greenwich time (GMT) in hours, without "GMT" word
• S: English ordinal suffix for the day of the month, 2 characters

基本用法：

• new Date().format("yyyy/mm/dd");
• new Date().strtotime("+1 day");
• new Date().strtotime("next month +1 day");
• new Date().strtotime("last sunday");
• new Date().strtotime("last sunday").format("yyyy/mm/dd");