# assertContainsOnlyInstancesOf() >[info] ## assertContainsOnlyInstancesOf(string $classname, Traversable|array $haystack[, string $message = '']) 当 `$haystack` 并非仅包含类 `$classname` 的实例时报告错误，错误讯息由 `$message` 指定。 **Example A.9. assertContainsOnlyInstancesOf() 的用法** ~~~ <?php class ContainsOnlyInstancesOfTest extends PHPUnit_Framework_TestCase { public function testFailure() { $this->assertContainsOnlyInstancesOf('Foo', array(new Foo(), new Bar(), new Foo())); } } ?> ~~~ ~~~ phpunit ContainsOnlyInstancesOfTest PHPUnit 5.0.0 by Sebastian Bergmann and contributors. F Time: 0 seconds, Memory: 5.00Mb There was 1 failure: 1) ContainsOnlyInstancesOfTest::testFailure Failed asserting that Array ([0]=> Bar Object(...)) is an instance of class "Foo". /home/sb/ContainsOnlyInstancesOfTest.php:6 FAILURES! Tests: 1, Assertions: 1, Failures: 1. ~~~