public void Should_RemoveAllItemFromDropzone() { var service = new DragDropService(null); DraggableItem isDelegateCalled = null; service.RegisterDropzone(1, new DropzoneOptions() { Name = "Testzone" }); var draggable = new DraggableItem(service) { Id = 1, DropzoneId = 1, Tag = new { Test = "OnDropTagTest" }, OnDrop = (d) => isDelegateCalled = d }; var draggable1 = new DraggableItem(service) { Id = 1, DropzoneId = 1, Tag = new { Test = "OnDropTagTest" }, OnDrop = (d) => isDelegateCalled = d }; var draggable2 = new DraggableItem(service) { Id = 1, DropzoneId = 1, Tag = new { Test = "OnDropTagTest" }, OnDrop = (d) => isDelegateCalled = d }; service.RegisterDraggableForDropzone(draggable); service.RegisterDraggableForDropzone(draggable1); service.RegisterDraggableForDropzone(draggable2); Assert.IsTrue(service.HasDropzoneDraggables(1)); service.ClearDropzone("Testzone"); Assert.IsFalse(service.HasDropzoneDraggables(1)); }