我有以下正则表达式：
once|every (?:(?:([1-9][0-9]?[0-9]? )?(hours?|days?))|(?:(?:(?:(1st|2nd|3rd|4th|5th))? ?(monday|tuesday|wednesday|thursday|friday|saturday|sunday)?)|((?:[1-9]|[1-2][0-9]|3[0-1])(?:st|nd|rd|th))) ?(?:(of the month)? ?(?:(?:repeated every )([2-9][0-9]?[0-9]?) (weeks|months))?)?)
这适用于我需要的大部分内容,但不适用于以下字符串…
Every 20th of the month
以下工作很棒……
Once Every hour Every day Every 2 hours Every 2 days Every Monday Every 1st of the month Every 1st of the month repeated every 3 months Every 2nd Monday of the month Every 2nd Monday of the month repeated every 3 months
你能帮我吗？
谢谢
解决方法
问题是(？:(？:( 1st | 2nd | 3rd | 4th | 5th))？(星期一|星期二|星期三|星期四|星期五|星期六|星期日)？)部分：它可能匹配一个空字符串.因此,它总是“赢”.
您可以通过删除来修复它吗？星期日之后的量词,使星期几成为强制性模式.见this regex demo.
另外,如果你用正则表达式检查的字符串是独立的,你可以用^(?:和)$模式将整个模式括起来,使它们匹配整个模式.见this regex demo.
