public void TestThatPassingInNullForTheUriReturnsEmptyStringForEachElement()
{
string sSipURI = null;
string sExpectedUsername = "";
string sExpectedDomain = "";
string sExpectedPort = "";
Assert.That(m_sipFormatter.GetUsernameFromUri(sSipURI), Is.EqualTo(sExpectedUsername));
Assert.That(m_sipFormatter.GetDomainFromUri(sSipURI), Is.EqualTo(sExpectedDomain));
Assert.That(m_sipFormatter.GetPortFromUri(sSipURI), Is.EqualTo(sExpectedPort));
}