public virtual void TestIndexOf() { Collection4 c = new Collection4(); Assert.AreEqual(-1, c.IndexOf("notInCollection")); c.Add("one"); Assert.AreEqual(-1, c.IndexOf("notInCollection")); Assert.AreEqual(0, c.IndexOf("one")); c.Add("two"); c.Add("three"); Assert.AreEqual(0, c.IndexOf("one")); Assert.AreEqual(1, c.IndexOf("two")); Assert.AreEqual(2, c.IndexOf("three")); Assert.AreEqual(-1, c.IndexOf("notInCollection")); }