try { $db = new PDO('mysql:host=localhost;dbname=mydatabase', $user, $pass); } catch (PDOException $e) { echo "Could not connect to database: " . $e->getMessage(); // log error to file or database }
$filename = 'myfile.txt'; if (!file_exists($filename)) { echo "File does not exist"; // handle error, e.g. create a new file or notify user }This code checks if a file called myfile.txt exists in the current directory. If it does not exist, an error message is displayed and the application can handle the error in a way that makes sense for its use case. Overall, the package library used in the examples depends on how the application was designed and what packages were used to build it.