How can check a php file is successfully included?

Question

I want to check if 'dbas.php' is included in 'ad.php'. I wrote the code -

ad.php

<?php if(file_exists("dbas.php") && include("dbas.php")){
// some code will be here
}
else{echo"Database loading failed";}
?>

I successfully tested the file_exists() part but don't know if the include() will work well or not, cause I tried in localhost and if the file is in directory then it never fails to include. So I don't know how this code would behave in the server if much traffic be there. So please tell me is my code correct ?

-Thanks.

Solved: Thank you so much for your answers.

Answer 1

Using php's require method is more suitable if you want to be absolutely sure that the file is included. file_exists only checks if the file exists, not if it's actually readable.

require will produce an error if inclusion fails (you can catch the error, see Cerbrus' answer).

Edit:

However, if you don't want the script to halt if the inclusion fails, use the method is_readable along with file_exists, like:

if( file_exists("dbas.php") && is_readable("dbas.php") && include("dbas.php")) {
    /* do stuff */
}

Answer 2

Simply use require:

try {
    require 'filename.php';
} catch (Exception $e) {
    exit('Require failed! Error: '.$e);
    // Or handle $e some other way instead of `exit`-ing, if you wish.
}

Something that wasn't mentioned yet: you could add a boolean, like:

$dbasIncluded = true;

In your dbas.php file, then check for that boolean in your code. Although generally, if a file doesn't include properly, you'd want php to hit the brakes, instead of rendering the rest of the page.