Regular expression online verification tool
1,Implement online custom regular expressions to extract text content
2,Validate any regular expression
What exactly is a regular expression?
When writing programs or web pages that process strings, there is often a need to find strings that meet certain complex rules. Regular expressions are the tools used to describe these rules. In other words, regular expressions are code that records text rules.
Common metacharacters
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Code
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Description
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.
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Matches any character except newline
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\w
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Match letters or numbers or underscores
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\s
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Matches any whitespace
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\d
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Matching numbers
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\b
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Match the beginning or end of a word
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^
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Match the beginning of a string
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$
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Match end of string
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Common qualifiers
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Code / syntax
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Description
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*
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Repeat zero or more times
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+
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Repeat one or more times
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?
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Repeat zero or one time
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{n}
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Repeat n times
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{n,}
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Repeat n or more times
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{n,m}
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Repeat n to m times
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Common antonyms
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Code / syntax
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Description
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\W
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Matches any characters that are not letters, numbers, underscores, or Chinese characters
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\S
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Matches any character that is not a space character
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\D
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Matches any non-digit character
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\B
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Matches where the word is not beginning or ending
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[^x]
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Matches any character except x
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[^aeiou]
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Matches any character except the letters aeiou
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