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PHP class_parents() Function: Usage and Examples

PHP class_parents() Function: Usage and Examples: Lists parent classes rather than interfaces or traits. See three examples and important limitations.

1 views Published Oct 17, 2026 Updated Oct 17, 2026 admin

The PHP class_parents API performs a focused operation on an object or value. The examples below show its effect on actual data.

Lists parent classes rather than interfaces or traits.

What Is class_parents in PHP?


Lists parent classes rather than interfaces or traits.

Syntax:

class_parents($object_or_class, bool $autoload = ...): array|false

The method accepts the following parameters:

  • $object_or_class — Required. A PHP parameter named object_or_class; the examples below show a supported value.
  • $autoload — Optional. A bool parameter named autoload; the examples below show a supported value.

Return type declared by PHP: array|false. The value or side effect is demonstrated in the examples below.

Example 1: Basic Usage


This example uses a small input to make the main behavior visible.

<?php

class BaseEntity {}
class InvoiceEntity extends BaseEntity {}
print_r(class_parents(InvoiceEntity::class));

Output:

Array
(
    [BaseEntity] => BaseEntity
)

Lists parent classes rather than interfaces or traits.

Example 2: A Different Input


A different set of values shows the same operation in another situation.

<?php

class BaseEntity {}
class InvoiceEntity extends BaseEntity {}
print_r(class_parents(InvoiceEntity::class));
// The output reflects definitions in this PHP process.

Output:

Array
(
    [BaseEntity] => BaseEntity
)

Classes without a parent return an empty array.

Practical Example: Applying the Feature


This example shows an application-style use of the feature, with its surrounding setup visible.

<?php

class BaseEntity {}
class InvoiceEntity extends BaseEntity {}
print_r(class_parents(InvoiceEntity::class));
// Use this result while deciding how to handle optional application features.

Output:

Array
(
    [BaseEntity] => BaseEntity
)

The code is shown for learning. Adjust the class names, inputs and error handling to suit your application.

Important Behavior and Edge Cases


  • Classes without a parent return an empty array.
  • Lists parent classes rather than interfaces or traits.
  • Observe differences in empty inputs, invalid states and optional extension availability where relevant.

Comparison With Related Approaches


ApproachImportant Difference
class_parentsLists parent classes rather than interfaces or traits.
class_implements()class_parents() lists inherited classes, while class_implements() lists interfaces.

Common Beginner Mistakes


MistakeCorrect Approach
Ignoring the documented state or precondition of class_parentsClasses without a parent return an empty array.
Expecting a different type of resultRead the declared return type and distinguish returned values from changes to the source object.
Assuming a related API works identicallyclass_parents() lists inherited classes, while class_implements() lists interfaces.

Key Takeaways


  • Lists parent classes rather than interfaces or traits.
  • Classes without a parent return an empty array.
  • Use the example that matches the values, runtime version and dependencies in your application.

class_parents is useful when its behavior matches the data structure and lifecycle of your PHP application. Choose it with a clear understanding of its preconditions and returned values.

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