Everything About Exceptions in PHP

Using exceptions in PHP is one of the most critical aspects for developers to manage errors effectively. Previously, developers commonly relied on PHP's built-in error handling functions like die() and error_log() for error management. However, these methods provided limited options for handling various types of errors and delivering meaningful information to users.

With the introduction of exceptions in PHP 5, we shifted from traditional error handling methods to utilizing exception handling concepts. This evolution allowed developers to manage errors in a more structured and understandable way. When an error occurs, the developer can throw an exception and handle it elsewhere in the code appropriately.

Exception classes in PHP have a high level of abstraction, and you can create your specific exceptions inheriting from the base class Exception. With this approach, you can define more specific details, such as custom messages and error codes, improving the information available at runtime.

Let's take a closer look at a real example of managing exceptions in PHP. In this example, we attempt to divide a number by zero, which would lead to a mathematical error. By using exceptions, we can handle this issue more accurately and precisely.

<?php

function divide($dividend, $divisor) {
    if($divisor == 0) {
        throw new Exception("Division by zero.");
    }
    return $dividend / $divisor;
}

try {
    echo divide(10, 0);
} catch (Exception $e) {
    echo "Caught exception: ",  $e->getMessage();
}

?>

Error Explanation Line by Line

function divide($dividend, $divisor): This function takes two input parameters for division.

if($divisor == 0): It checks whether the divisor is zero or not.

throw new Exception("Division by zero."): If the divisor is zero, it throws a new exception with the message "Division by zero.".

return $dividend / $divisor: If the divisor is not zero, it returns the result of the division.

try {: This block attempts to execute the division function.

catch (Exception $e): Handles any exception that occurs in the try block.

echo "Caught exception: ", $e->getMessage(): Displays a message to the user containing the exception message.