Special characters in regular expressions
Character implication
\ As a turn, that is, the characters usually after "\" are not interpreted in the original sense, such as the/b/matching character "B", when B is preceded by a backslash/\b/, to
The checksum is all made up of numbers
Funtin Isigit (s) {var patrn=/^[0-9]{1,20}$/; if (!patrn.x (s)) Rturn Fals Rturn Tru}
Javasript Form validation mail to determine whether an input is mailbox mail and implemented through regular expressions.
The regular expression of JSWhether the checksum is all made up of numbersCodefunction IsDigit (s){var patrn=/^[0-9]{1,20}$/;if (!patrn.exec (s)) return falsereturn True}Check login name: Only 5-20 entries begin with a letter, can be numbered, "_", "
// Check whether it is composed of digits[Code] function isDigit (s) {var patrn =/^ [0-9] {1, 20} $/; if(! Patrn.exe c (s) return false return true} [/code]
// Check Logon Name: You can enter only 5-20 strings starting with a letter, which can
Replace () is a simple replacement of characters.
ExampleCodeAs follows:
It only replaces the first letter. However, if you add a regular expression, the results will be different! Replace () supports regular expressions. It can match
Document directory
C {n}
C {m, n}
C {n ,}
*, + ,?
Greedy and non-greedy
Matching results of sub-regular expressions are not recorded
Forward pre-Query
?!
Global match, modifier g
Case-insensitive, modifier I
The end of the first line,
JavaScript's RegExp objects and string objects define methods that use regular expressions to perform powerful pattern matching and text retrieval and substitution functions.
In JavaScript, regular expressions are represented by a RegExp object. Of
The regular expression is a regular expression. It seems that English is better understood than Chinese, that is, the regular expression is checked for non-conforming characters !! Regular expressions have a powerful and complex object RegExp, which
The regular expression is a regular expression. It seems that English is better understood than Chinese, that is, checking expression charactersNot compliant !! Regular expressions have a very powerful and complex object Regexp. In javascript1.2.Let'
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