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基础学识: 正则表达式 (Regular Expression) #20

Open lewenweijia opened 4 years ago

lewenweijia commented 4 years ago

(?: ) : 非捕获分组(non-capture group) (?! ) : 反前瞻 (negative lookahead) (?= ) : 正前瞻 (lookahead) (?<= ): 正后瞻 (lookbehind) (?<! ): 反后瞻 (negative lookbehind)

用例:

'hello world'.replace(/[lor]/g, '$1-')
'hello world'.replace(/([lor])/g, (_, c) => c.toUpperCase())

/hello(?!better)/.test('hello world') // true
/hello(?!better)/.test('hellobetter') // false

/(?<!worst) world/.test('better world') // true
/(?<!worst) world/.test('worst world') // false