I use this regular expression to validate Twitter username. If a user enters a valid Twitter username that includes @, it will be matched.
/(?<=^|(?<=[^a-zA-Z0-9-_\.]))@([A-Za-z]+[A-Za-z0-9-_]+)/g
Matches:
- @regex_pattern
- @regex-pattern
Non-matches:
- @regex/pattern
- regexpattern
- regexpattern@
See Also:
- Username Regular Expression
- Name Validation Regular Expression
- Hashtag (#) Regular Expression
- Regex To Match All #hashtags In A String