单元测试预计在调用MSTest上的异步操作时抛出异常

下面的源代码是关于我的问题的示例代码片段。我期望在调用异步操作时发生异常。

单元测试

[TestMethod()]
[ExpectedException(typeof(Exception))]
public void OperateAsyncTest()
{
    //Arrange
    var testAsyncClass = new TestAsyncClass();
    //Act
    testAsyncClass.OperateAsync();
}

代码

public class TestAsyncClass
{
    public void OperateAsync()
    {
        ThreadPool.QueueUserWorkItem( obj =>{
            throw new Exception("an exception is occurred.");
        });
    }
}

但是，MsTest不能捕获异常，因为可能测试线程与抛出异常的线程不同。如何解决这个问题?任何想法?

下面的代码是我的变通方法，但它既不聪明也不优雅。

解决方案

[TestClass()]
public class TestAsyncClassTest
{
    private static Exception _exception = new Exception();
    private static readonly EventWaitHandle ExceptionWaitHandle = new AutoResetEvent(false);
    static TestAsyncClassTest()
    {
        AppDomain.CurrentDomain.UnhandledException += CurrentDomain_UnhandledException;
    }
    static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
    {
        _exception = (Exception)e.ExceptionObject;
        ExceptionWaitHandle.Set();
    }

    [TestMethod()]
    [ExpectedException(typeof(Exception))]
    public void OperateAsyncTest()
    {
        //Arrange
        var testAsyncClass = new TestAsyncClass();
        //Act
        lock(_exception)
        {
            testAsyncClass.OperateAsync();
            ExceptionWaitHandle.WaitOne();
            throw _exception;
        }
    }
}

public class TestAsyncClass {
    public Task OperateAsync() {
        return Task.Factory.StartNew(
            () => {
                throw new Exception("an exception is occurred.");
            }
        );
    }
}
[TestClass]
public class TestAsyncClassTest {
    [TestMethod]
    [ExpectedException(typeof(AggregateException))]
    public void OperateAsyncTest() {
        var testAsyncClass = new TestAsyncClass();
        testAsyncClass.OperateAsync().Wait();
    }
}