public void Flatten_Model_ToString() { var vehicle = new Car() { Ids = new int[] { 1, 2, 3 }, Name = "Nissan Primera 1.8 Flare 5dr", Colour = "Red", Engine = new Engine() { EngineSize = "1.8L", Measure = new Type() { Name = "New measure Type" } } }; var output = vehicle.ObjectToString <Car>(); Assert.Equal("Name:Nissan Primera 1.8 Flare 5dr Colour:Red |Tests.Car|EngineSize:1.8L |Tests.Engine|Name:New measure Type Ids:123", output); }