The filter_SSL() WordPress PHP function formats a URL to use https. It can be particularly useful when you need to ensure that a specific URL is always accessed securely.
Usage
You can use this function to convert a given URL to its https version. Here’s a generic example:
$url = "http://example.com"; $secure_url = filter_SSL($url); echo $secure_url; // Outputs: https://example.com
Parameters
$url(string): The URL that needs to be converted to https.
More information
See WordPress Developer Resources: filter_SSL()
Please note that the filter_SSL() function is not natively available in WordPress. It’s a custom function that you can create in your theme or plugin. It’s a common practice to create such a function when you need to enforce https on specific URLs.
Examples
Changing a website URL to https
If your website has been recently moved to https and you have a URL stored in your database, you can use filter_SSL() to ensure the URL is accessed securely.
// Assume you have a URL from the database $db_url = "http://old-website.com"; // Use the filter_SSL function to convert it to https $secure_db_url = filter_SSL($db_url); // Now, you can use the secure URL for any purpose echo $secure_db_url; // Outputs: https://old-website.com
Generating secure links to other pages on your site
When creating links to other pages on your site, use filter_SSL() to ensure they’re always accessed securely.
// Assume you have a relative URL to a page on your site $relative_url = "/about-us"; // Generate the full URL $full_url = "http://my-website.com" . $relative_url; // Use the filter_SSL function to convert it to https $secure_url = filter_SSL($full_url); // Now, you can use the secure URL in your HTML echo '<a href="' . $secure_url . '">About Us</a>'; // Outputs: <a href="https://my-website.com/about-us">About Us</a>
Converting URLs in an array
If you have an array of URLs that need to be converted to https, you can use filter_SSL() with array_map().
// Assume you have an array of URLs
$urls = ["http://website1.com", "http://website2.com", "http://website3.com"];
// Use array_map with filter_SSL to convert all URLs to https
$secure_urls = array_map('filter_SSL', $urls);
// Now, all URLs in $secure_urls are https
print_r($secure_urls);
/* Outputs:
Array
(
[0] => https://website1.com
[1] => https://website2.com
[2] => https://website3.com
)
*/
Working with URLs from a form submission
If you’re handling a form submission that includes a URL, use filter_SSL() to ensure the URL is secure before storing it in the database.
// Assume $_POST['website'] contains a URL from a form submission $submitted_url = $_POST['website']; // Use the filter_SSL function to convert it to https $secure_url = filter_SSL($submitted_url); // Now, you can store $secure_url in the database