Php uses the filter function to verify the mailbox, url, and IP address

In php programs, regular expressions are generally used to verify email addresses, IP addresses, and URLs. In fact, some Built-in validation rules are provided in php. The following example describes how to use the built-in filter function of php to verify email, ip, and URL.

1. verify email

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

2. Verify the url address

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

3. Verify the IP address

$ Url = '192. 168.0.1 '; $ result = filter_var ($ url, FILTER_VALIDATE_IP); var_dump ($ result); // output: string (11) '192. 168.0.1'

The filter function in php can also be used to verify floating-point numbers, integer numbers, and Boolean types. For details, 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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