Saturday 21 December 2013

How To Validate Email, URL And IP in PHP


How To Validate Email, URL And IP in PHP I know to most PHP programmers, this isn’t a big deal. I am going to show us, how to validate Email, URL and IP address using their respective PHP validation function.
It is very important input by users are validated before they are sent for processing. Not validating what users enter can lead to a very big security breach and could make your website susceptible to hackers. PHP has a large number of filters for validation and sanitization, but we’re only going to see that of the Email, URL and IP address.
Let’s take a look at these validation filters and how they work.

Validating Email:
Function :– filter_var($value, FILTER_VALIDATE_EMAIL)
<?php
 $email = "knowledgecorner@gmail.com";
 if (filter_var($email, FILTER_VALIDATE_EMAIL)) {
 echo "This ($email) email is valid.";
 }
 else {
 echo "This ($email) is not valid.";
 }
?>
Validating URL:
Function – filter_var($value, FILTER_VALIDATE_URL)
<?php
 $url = 'knowledgecorner.com';
 if (filter_var($url, FILTER_VALIDATE_URL)) {
 echo "This ($url) URL is valid.";
 }
 else {
 echo "This ($url) URL is not valid.";
 }
?>
Validating IP address:
Function – filter_var($value, FILTER_VALIDATE_IP)
<?php
 $ip = '10.199.212.2';
 if (filter_var($ip, FILTER_VALIDATE_IP)) {
 echo "This ($ip) IP address is valid.";
 }
 else {
 echo "This ($ip) IP address is not valid.";
 }
?>