What is the recommended approach for loading classes in PHP to avoid issues with abstract classes not being found?

When loading classes in PHP, it's important to use an autoloader to ensure that classes are loaded when they are needed. This helps avoid issues with abstract classes not being found because the autoloader can dynamically include the necessary files based on the class name. One common approach is to use a PSR-4 autoloader, which follows a specific directory structure to map namespaces to file paths.

// Autoloader function using PSR-4 standard
spl_autoload_register(function($className) {
    $prefix = 'Your\\Namespace\\Prefix\\';
    $baseDir = __DIR__ . '/src/';

    $len = strlen($prefix);
    if (strncmp($prefix, $className, $len) !== 0) {
        return;
    }

    $relativeClass = substr($className, $len);
    $file = $baseDir . str_replace('\\', '/', $relativeClass) . '.php';

    if (file_exists($file)) {
        require $file;
    }
});