public void Add_InvalidHtmlPassed_ReturnsBadRequest()
{
// Arrange
var idMissingItem = new Banner()
{
Html = "<h1>test<h1>",
Created = DateTime.Now
};
_controller.ModelState.AddModelError("Html", "Invalid");
// Act
var badResponse = _controller.Create(idMissingItem);
// Assert
Assert.IsType <BadRequestObjectResult>(badResponse.Result);
}