regular expression for negative 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.

// 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

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

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

PHP regular expression full manual, regular expression full manual Php regular expression full manual Preface Regular Expressions are cumbersome, but they are powerful. The application after learning will give you an absolute sense of accomplishment

The checksum is all made up of numbers Copy Code code as follows: function IsDigit (s) { var patrn=/^[0-9]{1,20}$/; if (!patrn.exec (s)) return false return True } Verify Login Name: Can only enter 5-20 letters

PHP Regular Expression full manual, regular expression full manual Full Manual of regular expressions for PHP Objective Regular expressions are cumbersome, but powerful, learned applications will give you an absolute sense of accomplishment in