How to verify an HTML element's class

I viewed this page 

http://docs.telerik.com/teststudio/testing-framework/write-tests-in-code/intermediate-topics-wtc/element-identification-wtc/finding-page-elements

and still am not sure on how to achieve my goal. I am trying to verify that an HTML element's class is "RequiredInvalid". All I have as a basis is the code to check that the element's value is not "".

[code]
Public Sub TX_1V_1D_Prod_ScriptTest_CodedStep()
        'Verify input 'FnameText' value 'Exact' ''.
        Assert.IsTrue(ArtOfTest.Common.CompareUtils.StringCompare(Pages.{page name here}.FrameObjTabFrame.FnameText.Value, "", ArtOfTest.Common.StringCompareType.Exact))
End Sub
[/code]

The element's name is FnameText. How would I tweak the above code to verify that FnameText's class is "RequiredInvalid"?

Thanks!