使用ASP.NET MVC 3 +数据注释和属性DateTime进行单元测试

Question

I'm on a project with DataAnnotations and ASP.NET MVC3. We use this solution to test the validations of "Date Annotions": http://gcbyjm.blogspot.com.br/2011/02/how-to-unit-test-dataannotations.html

I have problems to test a property "DateTime" of "ViewModel".

public class AchievementVM
{
    ...

    [Required(ErrorMessage = "The date field is required.")]
    [DataType(DataType.DateTime, ErrorMessage = "Invalid date.")]
    public DateTime Date { get; set; }

    ...
}

    [TestMethod]
    public void AchievementVMValidator_ShouldHaveErrorWhenDateIsInvalid()
    {
        // Arrange
        var achievementVM = new AchievementVM() { Date = ???? };

        // Act
        var errors = ValidationBuddy.GetErrors(achievementVM) as List<ErrorInfo>;

        // Assert
        ErrorInfo error = errors.Find(delegate(ErrorInfo e) { return e.ErrorMessage == "The date field is required."; });
        Assert.IsTrue(error != null);
    }

My question is how to pass the value of this property to simulate the ModelBind ERROR. In both situations, textbox empty and invalid data.

Thanks a lot!

Answer 1

If I understand your question correctly I think you should be testing action method that gets called by the view where the field is located. Like that you can pass invalid or empty values to the action method replicating empty or invalid values.

Answer 2

Remember that your view-model should be a representation of your view. So if your view allows a DateTime to not be entered (empty text box) then I think your view-model should have a nullable DateTime.

public DateTime? MyProperty { get; set; }

That way, in your unit test you can test for a null DateTime.

On your domain model this should be different as you dont want your database to receive a null DateTime so the domain model property should not be nullable. you view-model validation should stop the null date getting passed to the domain model or something converts it to a DateTime the domain model can handle. Maybe, for example, a null DateTime gets converted to DateTime.Now if your business requirements match this.

I hope this helps.