PHP - Filters

This extension filters data by either validating or sanitizing it. This is especially useful when the data source contains unknown data, like user supplied input. For example, this data may come from an HTML form.

Two Types of Filtering

Validation

Validation is used to validate or check if the data meets certain qualifications. For example, passing in FILTER_VALIDATE_EMAIL will determine if the data is a valid email address, but will not change the data itself.

Sanitization

Sanitization will sanitize the data, so it may alter it by removing undesired characters. For example, passing in FILTER_SANITIZE_EMAIL will remove characters that are inappropriate for an email address to contain. That said, it does not validate the data.

Filter Functions

Function	Description
filter_has_var	Checks if variable of specified type exists
filter_id	Returns the filter ID belonging to a named filter
filter_input_array	Gets external variables and optionally filters them
filter_input	Gets a specific external variable by name and optionally filters it
filter_list	Returns a list of all supported filters
filter_var_array	Gets multiple variables and optionally filters them
filter_var	Filters a variable with a specified filter

Validate Email Address Using FILTER_VALIDATE_EMAIL

<?php

	$email = "bharat.makwana@Veewom.com";
	if (!filter_var($email, FILTER_VALIDATE_EMAIL) === false) 
	{
	  echo("$email is a valid email address");
	} 
	else 
	{
	  echo("$email is not a valid email address");
	}

?>