ExpectedException Attribute Usage

Question

I am trying to work with the ExpectedException attribute in a C# UnitTest, but I am having issues getting it to work with my particular Exception

Answer 1

It will fail unless the type of exception is exactly the type you've specified in the attribute e.g

PASS:-

    [TestMethod()]
    [ExpectedException(typeof(System.DivideByZeroException))]
    public void DivideTest()
    {
        int numerator = 4;
        int denominator = 0;
        int actual = numerator / denominator;
    }

FAIL:-

    [TestMethod()]
    [ExpectedException(typeof(System.Exception))]
    public void DivideTest()
    {
        int numerator = 4;
        int denominator = 0;
        int actual = numerator / denominator;
    }

However this will pass ...

    [TestMethod()]
    [ExpectedException(typeof(System.Exception), AllowDerivedTypes=true)]
    public void DivideTest()
    {
        int numerator = 4;
        int denominator = 0;
        int actual = numerator / denominator;
    }