public void RegistrationWithNegativeData(string testName, params string[] assert) { var regPage = new RegistrationPage(this.driver); var user = AccessExcelData.GetRegistrationTestData(testName); regPage.NavigateTo(); regPage.FillRegistrationForm(user); var asserter = typeof(RegistrationPageAsserter).GetMethod(user.Asserter); int assertLenght = assert.Length; if (assertLenght == 1) { var assertString = String.Concat(assert); asserter.Invoke(null, new object[] { regPage, assertString }); } else { var str = assert; asserter.Invoke(null, new object[] { regPage, str }); } }