public void TestAddAndGetAndSet(HeaderType headerType)
{
string value1 = Guid.NewGuid().ToString();
string value2 = Guid.NewGuid().ToString();
INameValueCollection headers = this.CreateHeaders(headerType);
headers.Add(Key, value1);
Assert.AreEqual(value1, headers.Get(Key));
headers.Set(Key, value2);
Assert.AreEqual(value2, headers.Get(Key));
}