PHP Exception Handling: Try-Catch blocks for error messages

PHP Exception Handling: Exercise-4 with Solution

Write a PHP script that uses try-catch blocks to handle different types of exceptions and display appropriate error messages.

Sample Solution:

PHP Code :

<?php
try {
    // Code that may throw different types of exceptions
    $file = "test.txt";
    
    if (!file_exists($file)) {
        throw new RuntimeException("File does not exist.");
    }
    
    $handle = fopen($file, "r");
    if (!$handle) {
        throw new Exception("Error opening file.");
    }
    
    // Perform some file operations
    // ...
    
    fclose($handle);
} catch (RuntimeException $e) {
    // Handle RuntimeException
    echo "RuntimeException: " . $e->getMessage();
} catch (Exception $e) {
    // Handle generic Exception
    echo "Exception: " . $e->getMessage();
} finally {
    // Clean up resources or perform final actions
    echo "Script execution completed.";
}
?>

Sample Output:

RuntimeException: File does not exist.Script execution completed.

Explanation:

In the above exercise,

• We have a try block that contains code that throws different types of exceptions. We first check if a file exists using the file_exists() function and throw a RuntimeException if the file doesn't exist. Then, we try to open the file using fopen() and throw a generic Exception if the file opening fails.
• The catch blocks catch specific exception types (RuntimeException and Exception) and handle them separately. We display appropriate error messages using $e->getMessage().
• Finally, the finally block is optional and allows you to clean up resources or perform final actions. In this example, we simply display a message indicating script execution completion.

Flowchart:

PHP Code Editor:

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