PHP class_implements() Function: Usage and Examples

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

Returns interfaces implemented by a class, including inherited implementations.

What Is class_implements in PHP?

Returns interfaces implemented by a class, including inherited implementations.

Syntax:

class_implements($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

interface Exportable { public function export(): string; }
class CsvExport implements Exportable { public function export(): string { return "ok"; } }
print_r(class_implements(CsvExport::class));

Output:

Array
(
    [Exportable] => Exportable
)

Returns interfaces implemented by a class, including inherited implementations.

Example 2: A Different Input

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

<?php

interface Exportable { public function export(): string; }
class CsvExport implements Exportable { public function export(): string { return "ok"; } }
print_r(class_implements(CsvExport::class));
// The output reflects definitions in this PHP process.

Output:

Array
(
    [Exportable] => Exportable
)

The return value is an array; check membership with in_array() or isset() as appropriate.

Practical Example: Applying the Feature

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

<?php

interface Exportable { public function export(): string; }
class CsvExport implements Exportable { public function export(): string { return "ok"; } }
print_r(class_implements(CsvExport::class));
// Use this result while deciding how to handle optional application features.

Output:

Array
(
    [Exportable] => Exportable
)

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

Important Behavior and Edge Cases

• The return value is an array; check membership with in_array() or isset() as appropriate.
• Returns interfaces implemented by a class, including inherited implementations.
• Observe differences in empty inputs, invalid states and optional extension availability where relevant.

Comparison With Related Approaches

Common Beginner Mistakes

Key Takeaways

• Returns interfaces implemented by a class, including inherited implementations.
• The return value is an array; check membership with in_array() or isset() as appropriate.
• Use the example that matches the values, runtime version and dependencies in your application.

class_implements 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.