Why Does PHP Throw a 'Creating default object from empty value' Error?

Understanding PHP's "Creating Default Object from Empty Value" Error

PHP's "Creating default object from empty value" error often manifests when you access a property of a seemingly unset variable. This error is a result of PHP's strict error handling in versions 5.4 and beyond.

This error is triggered when PHP attempts to initialize a default object for a variable that is not yet an object or is explicitly set to NULL. For example:

$res = NULL;
$res->success = false;

In PHP 5.3 and earlier, this code would not produce any errors. However, in PHP versions 5.4 and above, E_STRICT warnings (or E_WARNINGs if you have error_reporting set to at least this level) are enabled, causing the "Creating default object from empty value" error.

Does $res Need to Be Declared First?

No, declaring $res as an object is not necessary. However, you must ensure that $res is an object before accessing its properties. To do this, you can either initialize it as an object of a specific class or use the generic stdClass object:

// Initialize as a specific class
$res = new MyClassName();

// Initialize as a generic object
$res = new \stdClass();

Once $res is an object, you can access and modify its properties without encountering the "Creating default object from empty value" error.

$res->success = false; // No error

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