php man page for interface_exists

INTERFACE_EXISTS(3)							 1						       INTERFACE_EXISTS(3)

interface_exists - Checks if the interface has been defined

SYNOPSIS
       bool interface_exists (string  $interface_name, [bool  $autoload = true])

DESCRIPTION
	Checks if the given interface has been defined.

PARAMETERS
	      o $interface_name
		- The interface name

	      o $autoload
		- Whether to call __autoload or not by default.

RETURN VALUES
	Returns TRUE if the interface given by $interface_name has been defined, FALSE otherwise.

EXAMPLES
       Example #1

	      interface_exists(3) example

	      <?php
	      // Check the interface exists before trying to use it
	      if (interface_exists('MyInterface')) {
		  class MyClass implements MyInterface
		  {
		      // Methods
		  }
	      }

	      ?>

SEE ALSO
       get_declared_interfaces(3), class_implements(3), class_exists(3).

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