Regular Expressions can be complicated as the expression gets longer. However, the individual pieces are simple. There’s just a lot of them. Below is a table of the more common characters available. All the available escape sequences are documented on php.net. Syntax Meaning Syntax Meaning \d any decimal digit: 0-9 \D any character that is … Read more » Regex Basics: The Syntax
Regular Expressions, or RegEx, are a must have skill. This tutorial will help you learn them, by analyzing a regex to validate if a number is between 0 and 255.