How to use PHP filter function to verify email, URL and IP address_PHP tutorial

When verifying emails, IP addresses or URLs in PHP programs, we generally use regular expressions to process them. In fact, there are some built-in special verification rules in PHP. Let's use an example to talk about how to use PHP's built-in filter function to verify email, IP and URL.

1. Verify email

$email='phpernote@163.com'; 
$result=filter_var($email,FILTER_VALIDATE_EMAIL); 
var_dump($result);
//输出：string(17) 'phpernote@163.com'

2. Verify url address

$url='http://www.phpernote.com/'; 
$result=filter_var($url,FILTER_VALIDATE_URL); 
var_dump($result);
//输出：string(25) 'http://www.phpernote.com/'

3. Verify IP address

$url='192.168.0.1'; 
$result=filter_var($url,FILTER_VALIDATE_IP); 
var_dump($result);
//输出：string(11) '192.168.0.1'

The filter function in php can also be used to verify floating point numbers, integer numbers, Boolean types, etc. For details, please refer to the filter function in the php manual or refer to the following article on this site

PHP filter_var() function Filter function

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