Regular Expressions
Common regexes
| purpose/match/validates | Regex |
|---|---|
| FQDN[(fully qualified domain name)][(from http://blog.gnukai.com/2010/06/fqdn-regular-expression/ which references RFC1035)] | (?=^.{1,254}$)(^(?:(?!\d|-)[a-zA-Z0-9\-]{1,63}(?<!-)\.?)+(?:[a-zA-Z]{2,})$) |
online tools
- Regexr – evaluates and explains regular expressions
- Regexpal – evaluates regexes
- Regex101 – online RegEx IDE
- Regex Crossword – game to learn regular expressions