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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
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
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'
Regular
Regular expression is regular expression, it seems that English is better than Chinese understand more, is to check expression characters do not conform to the rules!! Regular expressions have a very powerful and complex object regexp,
Http://www.jb51.net/article/25313.htmRegular expressions can:• Test a pattern for a string. For example, you can test an input string to see if there is a phone number pattern or a credit card number pattern in the string. This is called data
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,
Detailed explanation of Regular Expressions
Introduction
In short, regular expressions are a powerful tool for pattern matching and replacement. Its functions are as follows:Test a mode of a string. For example, you can test an input string to see
RegExp Direct volume and creation of objects
As with strings and numbers, it is obvious that the original type of direct quantity for each value in the program represents the same value. A new object is created each time the program runs with the
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