Question

Since attributes don’t inherit in C# (at least I didn’t think they did) – how does the following code still display the Hello popup when the MyTestMethod test is run:

[TestClass]
public class BaseTestClass {
    [TestInitialize]
    public void Foo() {
        System.Windows.Forms.MessageBox.Show("Hello");
    }
}

[TestClass]
public class TestClass : BaseTestClass {
    [TestMethod]
    public void MyTestMethod() {
        Assert.IsTrue(true);
    }
}

Answer 1

Attributes are inherited by default but this can be disabled – see AttributeUsage.Inherited

If you decorate the attribute definition with an AttributeUsage attribute, you can set this property:

[AttributeUsage(AttributeTargets.Class, Inherited = false)]
public class MyAttribute : Attribute
{
}