Public Event OnError As ErrorEventHandler

public event ErrorEventHandler OnError

using (WaitAndContinueWorker work = new WaitAndContinueWorker())
{
    SampleWork item = new SampleWork();
    item.WorkThrows = true;
    work.AddWork(item);

    ManualResetEvent mreError = new ManualResetEvent(false);
    Exception error = null;
    work.OnError += delegate(object o, ErrorEventArgs e) { error = e.GetException(); mreError.Set(); };

    item.Ready.Set();
    Assert.IsTrue(mreError.WaitOne(1000, false));
    Assert.IsTrue(error is ArgumentOutOfRangeException);
    Assert.IsTrue(((ArgumentOutOfRangeException)error).ParamName == "WorkThrows");
}

Using work As New WaitAndContinueWorker()
    Dim item As New SampleWork()
    item.WorkThrows = True
    work.AddWork(item)

    Dim mreError As New ManualResetEvent(False)
    Dim [error] As Exception = Nothing
    work.OnError += Function(o As Object, e As ErrorEventArgs) Do
        [error] = e.GetException()
        mreError.[Set]()
    End Function

    item.Ready.[Set]()
    Assert.IsTrue(mreError.WaitOne(1000, False))
    Assert.IsTrue(TypeOf [error] Is ArgumentOutOfRangeException)
    Assert.IsTrue((DirectCast([error], ArgumentOutOfRangeException)).ParamName = "WorkThrows")
End Using