Here's a very useful regular expression cheatsheet which I've found, and it may be very useful to those who are not really familiar with regular expression, especially for PHP's preg_replace and preg_match functions.

Regular ExpressionWill match...
fooThe string "foo"
^foo"foo" at the start of a string
foo$"foo" at the end of a string
^foo$"foo" when it is alone on a string
[abc]a, b, or c
[a-z]Any lowercase letter
[^A-Z]Any character that is not a uppercase letter
(gif|jpg)Matches either "gif" or "jpeg"
[a-z]+One or more lowercase letters
[0-9\.\-]Аny number, dot, or minus sign
^[a-zA-Z0-9_]{1,}$Any word of at least one letter, number or _
([wx])([yz])wy, wz, xy, or xz
[^A-Za-z0-9]Any symbol (not a number or a letter)
([A-Z]{3}|[0-9]{4})Matches three letters or four numbers


Published on 18 May 2012 - 8:30pm