A practical regular expression (Regex) cheat sheet covering character classes, anchors, lookaheads, quantifiers, and common pattern examples.
Frequently Asked Questions
Q1. What is Regular Expression (Regex)?
A Regular Expression (Regex) is a sequence of characters that defines a search pattern used in text searching, string replacement, and form input validation.
Q2. What is the difference between and + in Regex?
matches zero or more occurrences of the preceding element. + matches one or more occurrences.
Q3. How do I match an exact email address with Regex?
A standard email pattern is ^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$ which validates local-part, @ domain, and top-level domain.