正则表达式不是运算符 [英] Regex not operator
问题描述
正则表达式中是否存在NOT运算符?
就像在该字符串中一样:"(2001) (asdf) (dasd1123_asd 21.01.2011 zqge)(dzqge) name (20019)"
Is there an NOT operator in Regexes?
Like in that string : "(2001) (asdf) (dasd1123_asd 21.01.2011 zqge)(dzqge) name (20019)"
我要删除所有\([0-9a-zA-z _\.\-:]*\)
,而不要删除一年中的一个:(2001)
.
I want to delete all \([0-9a-zA-z _\.\-:]*\)
but not the one where it is a year: (2001)
.
因此正则表达式应返回的内容必须是:(2001) name
.
So what the regex should return must be: (2001) name
.
注意:\((?![\d]){4}[0-9a-zA-z _\.\-:]*\)
之类的东西对我不起作用((20019)
在某种程度上也匹配...)
NOTE: something like \((?![\d]){4}[0-9a-zA-z _\.\-:]*\)
does not work for me (the (20019)
somehow also matches...)
推荐答案
不,没有直接的not运算符.至少不是您希望的方式.
No, there's no direct not operator. At least not the way you hope for.
不过,您可以使用零宽度的负向超前查询:
You can use a zero-width negative lookahead, however:
\((?!2001)[0-9a-zA-z _\.\-:]*\)
(?!...)
部分的意思是仅在以下不匹配(因此:否定)的文本跟随(因此:lookahead)匹配时匹配.但是,它不匹配实际上不会消耗与其匹配的字符(因此为零宽度).
The (?!...)
part means "only match if the text following (hence: lookahead) this doesn't (hence: negative) match this. But it doesn't actually consume the characters it matches (hence: zero-width).
环顾四周实际上有4种组合,带有2个轴:
There are actually 4 combinations of lookarounds with 2 axes:
- lookbehind/lookahead:指定是否考虑在该点的之前或之后
- 正/负:指定字符必须匹配还是必须匹配.
- lookbehind / lookahead : specifies if the characters before or after the point are considered
- positive / negative : specifies if the characters must match or must not match.
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