PHP Built-in Functions PHP has over 1000 built-in functions that can be called directly, from within a script, to perform a specific task. Please check out our PHP reference for a complete overview of the PHP built-in functions.

The easiest and safest way to check whether an email address is well-formed is to use PHP's filter_var() function. In the code below, if the e-mail address is not well-formed, then store an error message:

The code below shows a simple way to check if the name field only contains letters, dashes, apostrophes and whitespaces.

The code below shows a way to check if a URL address syntax is valid (this regular expression also allows dashes in the URL).

Database column add remove and update by php array object.