Provide designer (propertygrid) support and control CodeDOM serialization for the CommandParameter property.

Author: KlausLoeffelmann

src/System.Windows.Forms/System/Windows/Forms/Controls/Buttons/ButtonBase.cs

@@ -221,10 +221,9 @@ public event EventHandler? CommandChanged
     ///  which is assigned to the <see cref="Command"/> property.
     /// </summary>
     [Bindable(true)]
-    [Browsable(false)]
-    [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
     [SRCategory(nameof(SR.CatData))]
     [SRDescription(nameof(SR.CommandComponentCommandParameterDescr))]
+    [TypeConverter(typeof(StringConverter))]
     public object? CommandParameter
     {
         get => _commandParameter;
@@ -238,6 +237,12 @@ public object? CommandParameter
         }
     }
 
+    private void ResetCommandParameter() => CommandParameter = null;
+
+    private bool ShouldSerializeCommandParameter() =>
+        _commandParameter is string parameter
+        && !string.IsNullOrEmpty(parameter);
+
     /// <summary>
     ///  Occurs when the value of the <see cref="CommandParameter"/> property has changed.
     /// </summary>

src/System.Windows.Forms/System/Windows/Forms/Controls/ToolStrips/ToolStripItem.cs

@@ -442,10 +442,9 @@ public event EventHandler? CommandChanged
     ///  which is assigned to the <see cref="Command"/> property.
     /// </summary>
     [Bindable(true)]
-    [Browsable(false)]
-    [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
     [SRCategory(nameof(SR.CatData))]
     [SRDescription(nameof(SR.CommandComponentCommandParameterDescr))]
+    [TypeConverter(typeof(StringConverter))]
     public object? CommandParameter
     {
         get => _commandParameter;
@@ -460,6 +459,12 @@ public object? CommandParameter
         }
     }
 
+    private void ResetCommandParameter() => CommandParameter = null;
+
+    private bool ShouldSerializeCommandParameter() =>
+        _commandParameter is string parameter
+        && !string.IsNullOrEmpty(parameter);
+
     /// <summary>
     ///  Occurs when the value of the <see cref="CommandParameter"/> property has changed.
     /// </summary>