Regular Expression

Introduction:

Regular expression is set of rules or predefined patterns.we can use regex for email addresses,phone numbers etc.

In php we have two sets of regular expression:

• POSFIX regex.
• PEARL style regex.

 

POSFIX:

POSFIX stands for Portable Operating System Interface for uniX , set of rules support by unix os.

PEARL Style Regex:

This regex structure follow the rules which use in PERL programming language.