Understanding Exceptions in PHP: Throw, Try, and Catch

Exception is a robust way to handle program errors in PHP, providing stack traces and controllable flow.

When an exception is thrown, subsequent code stops and PHP searches for a matching catch block; if none is found, a fatal error with “Uncaught Exception” is produced.

Example code demonstrates a function checkNum($number) that throws an Exception when the number is greater than 1, and shows the resulting fatal error when the exception is not caught.

To convert system errors into exceptions, set_error_handler() can be used before the error‑prone code.

The proper handling pattern uses try , throw , and catch :

function checkNum($number) {
    if ($number > 1) {
        throw new Exception("Value must be 1 or below");
    }
}
try {
    checkNum(2);
} catch (Exception $e) {
    echo 'File: ' . $e->getFile() . ' line: ' . $e->getLine() . '
';
    die('Message: ' . $e->getMessage());
}

The output shows the file, line number, and the exception message.

Code analysis: the function checks the value, throws an exception, the try block triggers it, the catch block receives the exception object $e , and the script prints the error details.