public void TestLogInterceptor() { var output = new StringWriter(); var builder = new ContainerBuilder(); builder.RegisterType <TestClass>().As <ITestClass>().Intercept(); builder.AttachInterceptorsToRegistrations(new LogInterceptor(output)); var container = builder.Build(); _testClass = container.Resolve <ITestClass>(); _testClass.TestMethod(1); var result = output.GetStringBuilder().ToString(); output.Dispose(); Assert.True(result.Contains("[INFO] Autofac.SmartInterceptors.Tests.Interceptors.LogInterceptorTests+ITestClass.TestMethod(val: 1)")); Assert.True(result.Contains("[INFO] Autofac.SmartInterceptors.Tests.Interceptors.LogInterceptorTests+ITestClass.TestMethod Returned: 1")); }