# System.Windows.Forms.Design

``` diff
 namespace System.Windows.Forms.Design {
     public sealed class EventHandlerService : IEventHandlerService {
-        public object GetHandler(Type handlerType);
+        public object? GetHandler(Type handlerType);
     }
     [CLSCompliantAttribute(false)]
     public class FolderNameEditor : UITypeEditor {
-        public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value);
+        public override object? EditValue(ITypeDescriptorContext? context, IServiceProvider provider, object? value);
-        public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context);
+        public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext? context);
         protected sealed class FolderBrowser : Component {
-            public string Description { get; set; }
+            [AllowNullAttribute]
+            public string Description { get; set; }
-            public DialogResult ShowDialog(IWin32Window owner);
+            public DialogResult ShowDialog(IWin32Window? owner);
         }
     }
     public class ImageListCodeDomSerializer : CodeDomSerializer {
-        public override object Deserialize(IDesignerSerializationManager manager, object codeObject);
+        public override object? Deserialize(IDesignerSerializationManager manager, object codeObject);
-        public override object Serialize(IDesignerSerializationManager manager, object value);
+        public override object? Serialize(IDesignerSerializationManager manager, object value);
     }
 }
```

