From 0076b6f3da3b3cfc68afb80d8c60309125665ac6 Mon Sep 17 00:00:00 2001
From: "Leaf Shi (BEYONDSOFT CONSULTING INC)" <v-leafshi@microsoft.com>
Date: Fri, 12 Jun 2026 15:25:24 +0800
Subject: [PATCH] Fix NumericUpDown button rendering regression when visual
 styles are disabled

---
 .../UpDown/UpDownBase.UpDownButtons.cs         | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/System.Windows.Forms/System/Windows/Forms/Controls/UpDown/UpDownBase.UpDownButtons.cs b/src/System.Windows.Forms/System/Windows/Forms/Controls/UpDown/UpDownBase.UpDownButtons.cs
index 35ad50fba98..57e8edf7ca4 100644
--- a/src/System.Windows.Forms/System/Windows/Forms/Controls/UpDown/UpDownBase.UpDownButtons.cs
+++ b/src/System.Windows.Forms/System/Windows/Forms/Controls/UpDown/UpDownBase.UpDownButtons.cs
@@ -270,7 +270,7 @@ protected override void OnPaint(PaintEventArgs e)
             int half_height = ClientSize.Height / 2;
 
             // Draw the up and down buttons
-            if (Application.IsDarkModeEnabled || !Application.RenderWithVisualStyles)
+            if (Application.IsDarkModeEnabled)
             {
                 Graphics cachedGraphics = EnsureCachedBitmap(
                     _parent._defaultButtonsWidth,
@@ -300,7 +300,7 @@ protected override void OnPaint(PaintEventArgs e)
                     _cachedBitmap,
                     new Point(0, 0));
             }
-            else
+            else if (Application.RenderWithVisualStyles)
             {
                 VisualStyleRenderer vsr = new(_mouseOver == ButtonID.Up
                     ? VisualStyleElement.Spin.Up.Hot
@@ -341,6 +341,20 @@ protected override void OnPaint(PaintEventArgs e)
                     new Rectangle(0, half_height, _parent._defaultButtonsWidth, half_height),
                     HWNDInternal);
             }
+            else
+            {
+                DrawScrollButton(
+                    e.GraphicsInternal,
+                    new Rectangle(0, 0, _parent._defaultButtonsWidth, half_height),
+                    ScrollButton.Up,
+                    _pushed == ButtonID.Up ? ButtonState.Pushed : (Enabled ? ButtonState.Normal : ButtonState.Inactive));
+
+                DrawScrollButton(
+                    e.GraphicsInternal,
+                    new Rectangle(0, half_height, _parent._defaultButtonsWidth, half_height),
+                    ScrollButton.Down,
+                    _pushed == ButtonID.Down ? ButtonState.Pushed : (Enabled ? ButtonState.Normal : ButtonState.Inactive));
+            }
 
             if (half_height != (ClientSize.Height + 1) / 2)
             {