C# 为什么正则表达式模式不';与文本不匹配?
我有一个正则表达式模式,我想将其与我的cron表达式匹配:C# 为什么正则表达式模式不';与文本不匹配?,c#,.net,regex,cron,C#,.net,Regex,Cron,我有一个正则表达式模式,我想将其与我的cron表达式匹配: string pattern = @"(((([0-9]|[0-5][0-9])(-([0-9]|[0-5][0-9]))?,)*([0-9]|[0-5][0-9])(-([0-9]|[0-5][0-9]))?)|(([\\*]|[0-9]|[0-5][0-9])/([0-9]|[0-5][0-9]))|([\\?])|([\\*]))[\\s](((([0-9]|[0-5][0-9])(-([0-9]|[0-5][0-9]))?,)*
string pattern = @"(((([0-9]|[0-5][0-9])(-([0-9]|[0-5][0-9]))?,)*([0-9]|[0-5][0-9])(-([0-9]|[0-5][0-9]))?)|(([\\*]|[0-9]|[0-5][0-9])/([0-9]|[0-5][0-9]))|([\\?])|([\\*]))[\\s](((([0-9]|[0-5][0-9])(-([0-9]|[0-5][0-9]))?,)*([0-9]|[0-5][0-9])(-([0-9]|[0-5][0-9]))?)|(([\\*]|[0-9]|[0-5][0-9])/([0-9]|[0-5][0-9]))|([\\?])|([\\*]))[\\s](((([0-9]|[0-1][0-9]|[2][0-3])(-([0-9]|[0-1][0-9]|[2][0-3]))?,)*([0-9]|[0-1][0-9]|[2][0-3])(-([0-9]|[0-1][0-9]|[2][0-3]))?)|(([\\*]|[0-9]|[0-1][0-9]|[2][0-3])/([0-9]|[0-1][0-9]|[2][0-3]))|([\\?])|([\\*]))[\\s](((([1-9]|[0][1-9]|[1-2][0-9]|[3][0-1])(-([1-9]|[0][1-9]|[1-2][0-9]|[3][0-1]))?,)*([1-9]|[0][1-9]|[1-2][0-9]|[3][0-1])(-([1-9]|[0][1-9]|[1-2][0-9]|[3][0-1]))?(C)?)|(([1-9]|[0][1-9]|[1-2][0-9]|[3][0-1])/([1-9]|[0][1-9]|[1-2][0-9]|[3][0-1])(C)?)|(L(-[0-9])?)|(L(-[1-2][0-9])?)|(L(-[3][0-1])?)|(LW)|([1-9]W)|([1-3][0-9]W)|([\\?])|([\\*]))[\\s](((([1-9]|0[1-9]|1[0-2])(-([1-9]|0[1-9]|1[0-2]))?,)*([1-9]|0[1-9]|1[0-2])(-([1-9]|0[1-9]|1[0-2]))?)|(([1-9]|0[1-9]|1[0-2])/([1-9]|0[1-9]|1[0-2]))|(((JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)(-(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?,)*(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)(-(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?)|((JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)/(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))|([\\?])|([\\*]))[\\s]((([1-7](-([1-7]))?,)*([1-7])(-([1-7]))?)|([1-7]/([1-7]))|(((MON|TUE|WED|THU|FRI|SAT|SUN)(-(MON|TUE|WED|THU|FRI|SAT|SUN))?,)*(MON|TUE|WED|THU|FRI|SAT|SUN)(-(MON|TUE|WED|THU|FRI|SAT|SUN))?(C)?)|((MON|TUE|WED|THU|FRI|SAT|SUN)/(MON|TUE|WED|THU|FRI|SAT|SUN)(C)?)|(([1-7]|(MON|TUE|WED|THU|FRI|SAT|SUN))?(L|LW)?)|(([1-7]|MON|TUE|WED|THU|FRI|SAT|SUN)#([1-7])?)|([\\?])|([\\*]))([\\s]?(([\\*])?|(19[7-9][0-9])|(20[0-9][0-9]))?| (((19[7-9][0-9])|(20[0-9][0-9]))/((19[7-9][0-9])|(20[0-9][0-9])))?| ((((19[7-9][0-9])|(20[0-9][0-9]))(-((19[7-9][0-9])|(20[0-9][0-9])))?,)*((19[7-9][0-9])|(20[0-9][0-9]))(-((19[7-9][0-9])|(20[0-9][0-9])))?)?)";
string text = "0 0 0 ? APR,MAY * 2020,2021,2022"
Match match = Regex.Match(text, pattern);
//the match output is: "0 0 0 ? APR,MAY *";
patter不知道这些年我就是不知道为什么
编辑:很抱歉上一篇文章中的javascript标记,现在我想解释一下为什么我会这样做。这是一个c#in.net项目,我想在前端检查一下,所以我考虑周到,这就是为什么我要添加javascript标记。很抱歉,这很糟糕。关于主题:我有一个cron表达式,如“stringtext”变量中的upper所示。我想检查给定的cron表达式是否有效。我们可以认为cron表达式有7个字段
“第二分钟小时数月数星期日”
所有字段之间都有空格。字符串模式覆盖除年份以外的所有字段。表达式是为POSIX正则表达式引擎编写/生成的。POSIX引擎试图匹配最长的子匹配 C#是一种.NET语言,使用基于PCRE的引擎。它试图匹配最左边的子匹配 例如,模式
[0-9]|[0-5][0-9]
将在POSIX引擎中尝试匹配“59”而不是“5”。PCRE引擎尝试匹配最左边的引擎,因此它只会尝试[0-9]
备选方案,并在成功时停止
在您的模式中,对于基于PCRE的发动机,备选方案的顺序不是最佳的,有时是错误的。下面是一个重写的模式:
( #1
(
([0-5][0-9]|[0-9])
(-([0-5][0-9]|[0-9]))?
,
)*
([0-5][0-9]|[0-9])
(-([0-5][0-9]|[0-9]))?
| ([*]|[0-5][0-9]|[0-9])
\/
([0-5][0-9]|[0-9])
| [?]
| [*]
)
[\s]
( #2
(
([0-5][0-9]|[0-9])
(-([0-5][0-9]|[0-9]))?
,
)*
([0-5][0-9]|[0-9])
(-([0-5][0-9]|[0-9]))?
| ([*]|[0-5][0-9]|[0-9])
\/
([0-5][0-9]|[0-9])
| [?]
| [*]
)
[\s]
( #3
(
([0-1][0-9]|[2][0-3]|[0-9])
(-([0-1][0-9]|[2][0-3]|[0-9]))?
,
)*
([0-1][0-9]|[2][0-3]|[0-9])
(-([0-1][0-9]|[2][0-3]|[0-9]))?
| ([*]|[0-1][0-9]|[2][0-3]|[0-9])
\/
([0-1][0-9]|[2][0-3]|[0-9])
| [?]
| [*]
)
[\s]
( #4
(
([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])
(-([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9]))?
,
)*
([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])
(-([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9]))?
C?
| ([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])
\/
([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])
C?
| LW
| L(-([1-2][0-9]|[3][0-1]|[0-9]))?
| [1-3][0-9]W
| [1-9]W
| [?]
| [*]
)
[\s]
( #5
(
(0[1-9]|1[0-2]|[1-9])
(-(0[1-9]|1[0-2]|[1-9]))?
,
)*
(0[1-9]|1[0-2]|[1-9])
(-(0[1-9]|1[0-2]|[1-9]))?
| (0[1-9]|1[0-2]|[1-9])
\/
(0[1-9]|1[0-2]|[1-9])
| (
(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)
(-(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?
,
)*
(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)
(-(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?
| (JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)
\/
(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)
| [?]
| [*]
)
[\s]
( #6
(
[1-7]
(-[1-7])?
,
)*
[1-7]
(-[1-7])?
| [1-7]\/[1-7]
| (
(MON|TUE|WED|THU|FRI|SAT|SUN)
(-(MON|TUE|WED|THU|FRI|SAT|SUN))?
,
)*
(MON|TUE|WED|THU|FRI|SAT|SUN)
(-(MON|TUE|WED|THU|FRI|SAT|SUN))?
C?
| (MON|TUE|WED|THU|FRI|SAT|SUN)
\/
(MON|TUE|WED|THU|FRI|SAT|SUN)
C?
| ([1-7]|MON|TUE|WED|THU|FRI|SAT|SUN)
[#]
[1-7]
| ([1-7]|MON|TUE|WED|THU|FRI|SAT|SUN)
(LW|L)?
| [?]
| [*]
)
( #7
[\s]
(
(19[7-9][0-9]|20[0-9][0-9])
(-(19[7-9][0-9]|20[0-9][0-9]))?
,
)*
(19[7-9][0-9]|20[0-9][0-9])
(-(19[7-9][0-9]|20[0-9][0-9]))?
| [\s]
(19[7-9][0-9]|20[0-9][0-9])
\/
(19[7-9][0-9]|20[0-9][0-9])
| [\s]
[*]
)?
或压缩成字符串:
var pattern = @"((([0-5][0-9]|[0-9])(-([0-5][0-9]|[0-9]))?,)*([0-5][0-9]|[0-9])(-([0-5][0-9]|[0-9]))?|([*]|[0-5][0-9]|[0-9])\/([0-5][0-9]|[0-9])|[?]|[*])[\s]((([0-5][0-9]|[0-9])(-([0-5][0-9]|[0-9]))?,)*([0-5][0-9]|[0-9])(-([0-5][0-9]|[0-9]))?|([*]|[0-5][0-9]|[0-9])\/([0-5][0-9]|[0-9])|[?]|[*])[\s]((([0-1][0-9]|[2][0-3]|[0-9])(-([0-1][0-9]|[2][0-3]|[0-9]))?,)*([0-1][0-9]|[2][0-3]|[0-9])(-([0-1][0-9]|[2][0-3]|[0-9]))?|([*]|[0-1][0-9]|[2][0-3]|[0-9])\/([0-1][0-9]|[2][0-3]|[0-9])|[?]|[*])[\s]((([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])(-([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9]))?,)*([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])(-([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9]))?C?|([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])\/([0][1-9]|[1-2][0-9]|[3][0-1]|[1-9])C?|LW|L(-([1-2][0-9]|[3][0-1]|[0-9]))?|[1-3][0-9]W|[1-9]W|[?]|[*])[\s](((0[1-9]|1[0-2]|[1-9])(-(0[1-9]|1[0-2]|[1-9]))?,)*(0[1-9]|1[0-2]|[1-9])(-(0[1-9]|1[0-2]|[1-9]))?|(0[1-9]|1[0-2]|[1-9])\/(0[1-9]|1[0-2]|[1-9])|((JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)(-(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?,)*(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)(-(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?|(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)\/(JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)|[?]|[*])[\s](([1-7](-[1-7])?,)*[1-7](-[1-7])?|[1-7]\/[1-7]|((MON|TUE|WED|THU|FRI|SAT|SUN)(-(MON|TUE|WED|THU|FRI|SAT|SUN))?,)*(MON|TUE|WED|THU|FRI|SAT|SUN)(-(MON|TUE|WED|THU|FRI|SAT|SUN))?C?|(MON|TUE|WED|THU|FRI|SAT|SUN)\/(MON|TUE|WED|THU|FRI|SAT|SUN)C?|([1-7]|MON|TUE|WED|THU|FRI|SAT|SUN)[#][1-7]|([1-7]|MON|TUE|WED|THU|FRI|SAT|SUN)(LW|L)?|[?]|[*])([\s]((19[7-9][0-9]|20[0-9][0-9])(-(19[7-9][0-9]|20[0-9][0-9]))?,)*(19[7-9][0-9]|20[0-9][0-9])(-(19[7-9][0-9]|20[0-9][0-9]))?|[\s](19[7-9][0-9]|20[0-9][0-9])\/(19[7-9][0-9]|20[0-9][0-9])|[\s][*])?";
您可能还希望在模式的开头添加^
,在模式的结尾添加$
。这确保在匹配的CRON表达式之前或之后没有额外的字符
var pattern = @"^((([0-5] ... [\s][*])?$";
这是JavaScript代码吗?如果是,它的语法有效吗?在我看来像C。不管怎样,我不清楚这里有什么问题。。。OP将提供更多的澄清(谢谢)。您想从regex捕获什么?请解释一下?
regex.Match
和@
前缀来自.net。请适当地标记您的问题。它起作用了。非常感谢。我对你的推荐投了赞成票,但它说公开展示至少需要15个声誉。