


How to Check File Existence on a Remote Server via URL in PHP?
Checking File Existence via URL
Determining whether a file resides on a remote server can be a perplexing task. Conventional methods like is_file() and file_exists(), designed for local files, prove ineffective in this scenario.
To tackle this challenge, a more suitable approach is required. PHP's get_headers function offers a straightforward solution.
By sending a request to the specified URL, get_headers retrieves the server's response headers. These headers provide valuable information, including HTTP status codes.
To ascertain whether a file exists, inspect the first element of the $headers array, $result[0]. A status code of "200 OK" indicates that the requested file is present on the server.
For added simplicity, encapsulate this functionality in a custom function, UR_exists, as the provided code snippet demonstrates.
Example Usage:
if(UR_exists("http://www.amazingjokes.com/")) echo "This page exists"; else echo "This page does not exist";
By leveraging get_headers, you can effortlessly validate the existence of files on remote servers, a feature that greatly enhances the capabilities of PHP in managing remote resources.
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