What can Regular Expressions do? A regular expression describes a pattern that is used to find and manipulate matching text in strings. Regular expressions resemble strings, but they can include special codes to describe patterns and repetition.
Above expression will be to match a valid e-mail address.
Yes, the Regular Expressions is very useful but write a regular is not an easy work, is there any tool help us to validate it in Flex? The answer is “Of course”. gskinner.com built a EXTREMELY useful Regular Expressions in Flex, we can test our own regExp with this tool.
Following is the url: http://gskinner.com/RegExr/, enjoy!