public void AsOffset_ChangeOffset_OnlyOffsetChanges() { TimeSpan plus3 = 3.Hours(), plus2 = 2.Hours(); DateTime threeOclockPlus3 = new DateTimeOffset(2008, 1, 1, 15, 0, 0, plus3).DateTime; assertOffSet(threeOclockPlus3.AsOffset(plus2), 1.January(2008).At(15.Hours()), plus2); }