Best Practice for Validating URLs - php

Question

I have a form to get some urls from users. Eg: Web Address, Facebook Address, Twitter Address, Google+ address etc... My problem is how I validate these urls when they submit the form. I tried to validate URL in PHP by using the FILTER_VALIDATE_URL or simply, using regular expression.
Here, I would like to know what are the best methods to get such a urls from users. Is it always good to let them to enter protocol? sometimes they may not know it is http, https, ftp, ftps.. etc. I think it is something hard to do some users.
I tried something like this using FILTER_VALIDATE_URL, But it always use protocol and sometime I am confusing how its work..
// validate url
$url = 'http://www.example.com';
if (filter_var( $url, FILTER_VALIDATE_URL)){
echo "<br>valid";
} else {
echo "<br>invalid";
}
OUTPUT : valid
// validate url
$url = 'hp://www.example.com';
if (filter_var( $url, FILTER_VALIDATE_URL)){
echo "<br>valid";
} else {
echo "<br>invalid";
}
OUTPUT : valid
// validate url
$url = 'http://example.com';
if (filter_var( $url, FILTER_VALIDATE_URL)){
echo "<br>valid";
} else {
echo "<br>invalid";
}
OUTPUT : valid
// validate url
$url = 'http://example.com?id=32&name=kamalani';
if (filter_var( $url, FILTER_VALIDATE_URL)){
echo "<br>valid";
} else {
echo "<br>invalid";
}
OUTPUT : valid
Can you tell me what are the best ways to get urls from user and how those validate?
Any comments are greatly appreciating..
Thank you.

Answer 1

You need to use regular expression to check valid url here.
Please try this :
$pattern = "/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&##\/%?=~_|!:,.;]*[-a-z0-9+&##\/%=~_|]/i";
$URL= 'http://example.com?id=32&name=kamalani';
if(preg_match($pattern, $URL) ){
echo "<br>valid";
} else{
echo "<br>invalid";
}
Output
valid