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This article introduces how to use regular expressions to obtain Chinese characters in strings. The content is very detailed. Interested friends can use it for reference. I hope it will be helpful to you.

Requirement: only get the "executor form for Editing initiating status" in attr. The path C:\ fakepath\ is not fixed, but can be C:\ fakepath\ hhh\ hhhh\

Resolve:

Var attr = C:\ fakepath\ Edit the executor form of the initiating state .png attr = title.split (".") [0]; / / intercept-- > "C:\ fakepath\ edit the executor form of the initiating state" var reg = new RegExp ('[\ u4e00 -\ u9fa5] + $','g'); / / define the rule: intercept the part ending in Chinese characters, + represents one or more Chinese characters attr = reg.exec (attr) / / intercept to-- > Edit the executor form alert (attr) of the initiating status

Supplement the regular basic syntax (source network):

1. Non-printing character

The character meaning\ cx matches the control character indicated by x. For example,\ cM matches a Control-M or carriage return. The value of x must be one of Amurz or aMuz. Otherwise, c is treated as a literal'c 'character. \ f matches a feed character. Equivalent to\ x0c and\ cL. \ nmatches a newline character. Equivalent to\ x0a and\ cJ. \ r matches a carriage return. Equivalent to\ x0d and\ cM. \ s matches any white space characters, including spaces, tabs, page breaks, and so on. Equivalent to [\ f\ n\ r\ t\ v]. \ s matches any non-white space character. Equivalent to [^\ f\ n\ r\ t\ v]. \ t matches a tab. Equivalent to\ x09 and\ cI. \ v matches a vertical tab. Equivalent to\ x0b and\ cK.

two。 Special character

The so-called special characters are some characters with special meaning, such as the * in "* .txt" mentioned above, which simply means the meaning of any string. If you want to find a file with a * in the file name, you need to escape *, that is, add a\ to it. Ls\ * .txt. Regular expressions have the following special characters.

The special character indicates that $matches the end of the input string. If the Multiline property of the RegExp object is set, $also matches'\ n'or'\ r'. To match the $character itself, use\ $. () marks the start and end positions of a subexpression. Subexpressions can be obtained for later use. To match these characters, use\ (and\). * matches the previous subexpression zero or more times. To match the * character, use\ *. + matches the previous subexpression one or more times. To match the + character, use\ +. . Matches any single character except the newline character\ n. To match., use\. [marks the beginning of a bracketed expression. To match [, use\ [. ? Matches the previous subexpression zero or once, or indicates a non-greedy qualifier. To play Standard PvP match? Characters, please use\? \ Mark the next character as either a special character, a literal character, a backward reference, or an octal escape character. For example,'n' matches the character'n'. \ n' matches the newline character. The sequence'\ 'matches "\", while'\ ('matches "(". ^ matches the start position of the input string unless used in a square bracket expression, where it indicates that the character collection is not accepted. To match the ^ character itself, use\ ^. {Mark the beginning of the qualifier expression. To match {, use\ {. | indicates a choice between the two items. To match |, use\ |.

You construct regular expressions in the same way as you create mathematical expressions. That is, a variety of metacharacters and operators are used to combine small expressions to create larger expressions.

The components of a regular expression can be a single character, a character collection, a character range, a choice between characters, or any combination of all these components.

3. Qualifier

Qualifiers are used to specify how many times a given component of a regular expression must appear to satisfy a match. Is there * or + or? Or {n} or {n,} or {n ~ m}.

*, + and? Qualifiers are greedy because they match as many words as possible, only adding one after them. Non-greedy or minimal matching can be achieved.

The qualifiers for regular expressions are:

The character description * matches the previous subexpression zero or more times. For example, zo* can match "z" and "zoo". * is equivalent to {0,}. + matches the previous subexpression one or more times. For example, 'zo+' can match "zo" and "zoo", but not "z". + is equivalent to {1,}. ? Matches the previous subexpression zero or once. For example, "do (es)?" Can match "do" in "do" or "does". ? It is equivalent to {0jue 1}. {n} n is a non-negative integer. Match the determined n times. For example,'o {2} 'does not match the' o'in 'Bob', but does match the two o in 'food'. {n,} n is a non-negative integer. Match at least n times. For example,'o {2,} 'does not match' o'in 'Bob', but does match all o in 'foooood'. O {1,}'is equivalent to 'oasis'. O {0,}'is equivalent to 'oval'. {n ·m} m} m and n are non-negative integers, where n

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