public void SetUp()
        {
            m_oGraph = new Graph();

            Debug.Assert(m_oGraph.Edges is EdgeCollection);

            IEdgeCollection oEdgeCollection = m_oGraph.Edges;

            Debug.Assert(oEdgeCollection.GetEnumerator() is
            EdgeCollection.Enumerator);

            m_oEnumerator =
            (EdgeCollection.Enumerator)oEdgeCollection.GetEnumerator();

            Debug.Assert(m_oGraph.Vertices is VertexCollection);

            m_oVertexCollection = m_oGraph.Vertices;
        }
        public void TearDown()
        {
            m_oEnumerator.Reset();

            m_oEnumerator = null;
            m_oGraph = null;
            m_oVertexCollection = null;
        }
 //*************************************************************************
 //  Constructor: EdgeCollectionEnumeratorTest()
 //
 /// <summary>
 /// Initializes a new instance of the <see
 /// cref="EdgeCollectionEnumeratorTest" /> class.
 /// </summary>
 //*************************************************************************
 public EdgeCollectionEnumeratorTest()
 {
     m_oEnumerator = null;
     m_oGraph = null;
     m_oVertexCollection = null;
 }