public void Add()
 {
     if (!IsEdit)
     {
         SelectedEquipment   = ActualEquipment.ToList();
         SelectedPermissions = ActualPermissions.ToList();
         string x = SpecializationService.Add(Name, Description, SelectedEquipment, SelectedPermissions);
         if (x == null)
         {
             TryClose();
         }
         else
         {
             Error = x;
         }
     }
     else
     {
         toEdit.Name         = Name;
         toEdit.Description  = Description;
         SelectedEquipment   = ActualEquipment.ToList();
         SelectedPermissions = ActualPermissions.ToList();
         string x = SpecializationService.Edit(toEdit, SelectedEquipment, SelectedPermissions);
         if (x == null)
         {
             TryClose();
         }
         else
         {
             Error = x;
         }
     }
 }
 public void ClickBackEquipment()
 {
     AvailableEquipment.AddRange(ActualEquipment.Where(x => x.IsSelected).ToList());
     ActualEquipment.RemoveRange(AvailableEquipment);
     NotifyOfPropertyChange(() => AvailableEquipment);
     NotifyOfPropertyChange(() => ActualEquipment);
 }