正则表达式 - 避免表达式中的字符串 [英] Regular Expression - Avoid a string in expression

问题描述

我正在尝试创建一个应该符合以下情况的正则表达式。
如果完全匹配单词'first，second，third'那么匹配应该失败 - 但是如果它周围有任何字符，那么字符串应该匹配。

I am trying to create a regex that should match following cases. if exact match of words 'first, second, third' then match should fail - but if there are any characters around it, then the string should be matched.

此外，我还需要避免字符串中的某些字符集。 [（）！=<>，] - 如果这些字符是字符串的一部分，那么匹配结果应该失败。

Also I need to avoid certain set of characters in the string. [()!=<>", ] - if these characters are part of string then match result should fail.

我看了几个例子&负面向前看但是还没有得到正确的正则表达式。

I looked at few examples & negative look ahead but did not get the right regex yet.

^(?!first$|second$|third$|fou rth$)[^()!=<>", ]+

所需的输出：

first - fail
second - fail
1first - pass
first1 - pass
1first1 - pass
fou rth - fail - it has space in between word and is from ignore list
newTest - pass
new(test - fail - since ( is not allowed character
space word - fail - since space is non allowed character

正则表达式需要支持不区分大小写的单词

The regex needs to support case insensitive words

任何帮助表示赞赏。我使用的是javascript。

Any help appreciated. I am using javascript.

推荐答案

试试这个正则表达式：

^（？！。* [（）！=<>，]）（？！（？：first | second | third ）$）。+ $

点击进行演示

说明：

• ^ - 断言字符串的开头


• （？！。* [（）！=<>，]） - 用于验证测试字符串不包含任何这些字符的否定预测 - （，），！， = ，< ，> ，，，


• （？！（？：first | second | third）$） - 此时我们处于测试字符串的开头。此位置不应紧跟（第一个或第二个或第三个）然后在字符串的末尾（ $ ）


• 。+ - 匹配任何字符的1 +次出现，但不匹配换行符


• $ - 断言字符串的结尾

• ^ - asserts the start of the string
• (?!.*[()!=<>", ]) - negative lookahead to validate that the test string does not contain any of these characters - (, ), !, =, <, >, ,,
• (?!(?:first|second|third)$) - At this moment we are at the beginning of the test string. This position should not be immediately followed by (first or second or third) and then by the end of the string($)
• .+ - matches 1+ occurrences of any character but not a newline character
• $ - asserts the end of the string

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