# assertInstanceOf() >[info] ## assertInstanceOf($expected, $actual[, $message = '']) 当 `$actual` 不是 `$expected` 的实例时报告错误，错误讯息由 `$message` 指定。 `assertNotInstanceOf()` 是与之相反的断言，接受相同的参数。 `assertAttributeInstanceOf()` 和 `assertAttributeNotInstanceOf()` 是便捷包装(convenience wrapper)，可以应用于某个类或对象的某个 `public`、`protected` 或 `private` 属性。 **Example A.24. assertInstanceOf() 的用法** ~~~ <?php class InstanceOfTest extends PHPUnit_Framework_TestCase { public function testFailure() { $this->assertInstanceOf('RuntimeException', new Exception); } } ?> ~~~ ~~~ phpunit InstanceOfTest PHPUnit 5.0.0 by Sebastian Bergmann and contributors. F Time: 0 seconds, Memory: 5.00Mb There was 1 failure: 1) InstanceOfTest::testFailure Failed asserting that Exception Object (...) is an instance of class "RuntimeException". /home/sb/InstanceOfTest.php:6 FAILURES! Tests: 1, Assertions: 1, Failures: 1. ~~~