Returns a string which is used in combo-boxes when none of the available combo-box items are selected.
You are viewing documentation for the legacy WPF Scheduler control. If you’re starting a new project, we strongly recommend that you use a new control declared in the DevExpress.Xpf.Scheduling namespace. If you decide to upgrade an existing project in order to switch to the updated scheduler control, see the Migration Guidelines document.
Use this value if you need to add a combo-box to provide editing of your specific properties when creating a custom Edit Appointment form.