class_exists()
class_exists() — Checks if the class has been defined.
Built-in function of PHP 8.5. The manual lists it as available in PHP 4, PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.
What it does
This function checks whether or not the given class has been defined.
Signature
class_exists(string $class, bool $autoload = true): bool
Parameters
| Parameter | Type | What it takes |
|---|---|---|
| $class | string | The class name. The name is matched in a case-insensitive manner. |
| $autoload | bool | Whether to autoload if not already loaded. |
Return value
Returns true if class is a defined class, false otherwise.
Example
A runnable snippet:
// Check that the class exists before trying to use it if (class_exists('MyClass')) { $myclass = new MyClass(); }
See also
function_exists(), enum_exists(), interface_exists(), get_declared_classes()
All PHP 8.5 built-in functions
Reference card built from the PHP manual page class_exists() (PHP documentation, CC BY 3.0). The page is generated from the manual, so the wording of the parameter and return value text follows php.net.