# System.Windows.Forms.Design.Behavior

``` diff
 namespace System.Windows.Forms.Design.Behavior {
     public sealed class BehaviorService : IDisposable {
-        public Behavior CurrentBehavior { get; }
+        public Behavior? CurrentBehavior { get; }
-        public event BehaviorDragDropEventHandler BeginDrag;
+        public event BehaviorDragDropEventHandler? BeginDrag;
-        public event BehaviorDragDropEventHandler EndDrag;
+        public event BehaviorDragDropEventHandler? EndDrag;
-        public event EventHandler Synchronize;
+        public event EventHandler? Synchronize;
-        public Behavior GetNextBehavior(Behavior behavior);
+        public Behavior? GetNextBehavior(Behavior behavior);
-        public Behavior PopBehavior(Behavior behavior);
+        public Behavior? PopBehavior(Behavior behavior);
     }
 }
```

