常用的正则表达式(en)

A Few Handy PHP Regular Expressions (RegEx)

 

Email Address:

'/^[^/W][a-zA-Z0-9_-]+(/.[a-zA-Z0-9_-]+)*/@[a-zA-Z0-9-]+(/.[a-zA-Z0-9-]+)*/.[a-zA-Z]{2,6}$/' 

Matches: john.doe@domain.edu This e-mail address is being protected from spam bots, you need JavaScript enabled to view it , john_doe@do.main.edu This e-mail address is being protected from spam bots, you need JavaScript enabled to view it , john-doe@do-main.edu This e-mail address is being protected from spam bots, you need JavaScript enabled to view it , john@doe.gov.us This e-mail address is being protected from spam bots, you need JavaScript enabled to view it

Domain Name 1: This only matched simple domain names

'/^([a-zA-Z0-9-]+)/.[a-zA-Z]{2,6}$/'

Matches: domain.com, domain.net
Non-matches: sub.domain.com, domain.uni.cc, domain.ne.jp

Domain Name 2: This only matches complex domain names

'/^([a-zA-Z0-9-]+)/.[a-zA-Z]{2,3}/.[a-zA-Z]{2}$/'

Matches: domain.uni.cc, domain.ne.jp
Non-matches: sub.domain.com, domain.com

Sub Domain: This will only match for a sub domain of the specified domain

'/^[a-zA-Z0-9-]+/.realdomainname/.com$/ '

Matches: help.realdomainname.com, subdomain.realdomainname.com
Non-matches: sub.domain.com, help.realdomainname.net

Sub Domain: This will only match for a sub domain of the specified domain

'/^[a-zA-Z0-9-]+/.realdomainname/.com$/ '

Matches: help.realdomainname.com, subdomain.realdomainname.com
Non-matches: sub.domain.com, help.realdomainname.net