regular expression for only numbers

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.

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

// 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 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, "_", "

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

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'

ObjectivesWithin 30 minutes, you can understand what a regular expression is and have some basic knowledge about it, so that you can use it in your own program or webpage. How to use this tutorial The most important thing is-Please give me 30