public void TestMapEntryHashCode() { HashMap <Object, Object> map = new HashMap <Object, Object>(10); Object key = 1; Object val = 2; map.Put(key, val); int expected = key.GetHashCode() ^ val.GetHashCode(); Assert.AreEqual(expected, map.GetHashCode()); key = 4; val = 8; map.Put(key, val); expected += key.GetHashCode() ^ val.GetHashCode(); Assert.AreEqual(expected, map.GetHashCode()); }