PHP exception handling: Handling specific exceptions

Last update on April 16 2025 12:57:00 (UTC/GMT +8 hours)

10. Specific Exception Handling Actions

Write a PHP program that uses a try-catch block to handle a specific exception and performs specific actions based on the exception type.

Sample Solution:

PHP Code :

<?php
class CustomException extends Exception {
    public function __construct($message, $code = 0, Throwable $previous = null) {
        parent::__construct($message, $code, $previous);
    }
    
    public function __toString() {
        return __CLASS__ . ": [{$this->code}]: {$this->message}\n";
    }
}

try {
    // Code that may throw a specific exception
    $number = "abc";
    
    if (!is_numeric($number)) {
        throw new CustomException("Invalid number.");
    }
    
    $result = 200 / $number;
    echo "Result: " . $result;
} catch (CustomException $e) {
    // Handle CustomException
    echo "CustomException: " . $e->getMessage();
    // Perform specific actions for CustomException
    // ...
} catch (Exception $e) {
    // Handle generic Exception
    echo "Exception: " . $e->getMessage();
}
?>

Sample Output:

CustomException: Invalid number

Explanation:

In the above exercise,

We have a try block that contains code that throws a specific exception. We check if the $number is numeric using is_numeric() and throw a CustomException if it's not.
The first catch block catches the CustomException specifically and handles it separately. It displays an appropriate error message using $e->getMessage() and can perform specific actions for the CustomException.
The second catch block catches a generic Exception if another type of exception occurs. It displays an appropriate error message using $e->getMessage().

Flowchart:

For more Practice: Solve these Related Problems:

Write a PHP script that throws a specific exception based on a given error code and catches it to perform a corresponding recovery action.
Write a PHP function that processes an input and throws different exceptions for distinct error conditions, then handles each using specific catch blocks.
Write a PHP program to simulate an operation where a specific exception is thrown and then a custom action is taken in the catch block before rethrowing.
Write a PHP script to implement a try-catch structure that distinguishes errors based on exception messages and executes alternative code paths accordingly.

PHP Code Editor:

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