public void Visa_card_number_invalid()
{
//Arrange
CardViewModel fakeModel = new CardViewModel()
{
Number = "4123123412341234",
Month = 12,
Year = 2018
};
_controller.ModelState.AddModelError("Card", "Invalid");
//Act
var actionResult = _controller.Card(fakeModel);
var objectResult = actionResult as ObjectResult;
var modelState = objectResult.Value as dynamic;
//Assert
Assert.IsType <BadRequestObjectResult>(actionResult);
Assert.NotNull(objectResult?.Value);
Assert.True(modelState?.ContainsKey("Card"));
}