fix TextBoxBase related Controls backColor problems

Epica3055 · Epica3055 · commit 1a8e8b1e3d4a · 2025-08-19T09:11:20.000+08:00
diff --git a/src/System.Windows.Forms/System/Windows/Forms/Controls/TextBox/TextBoxBase.cs b/src/System.Windows.Forms/System/Windows/Forms/Controls/TextBox/TextBoxBase.cs
@@ -949,7 +949,8 @@ private void EnsureReadonlyBackgroundColor(bool value)
     {
         // If we have no specifically defined back color, we set the back color in case we're in dark mode.
         if (Application.IsDarkModeEnabled
-            && DarkModeRequestState is true)
+            && DarkModeRequestState is true
+            && !ShouldSerializeBackColor())
         {
             base.BackColor = value ? SystemColors.ControlLight : SystemColors.Window;
             Invalidate();

Original file line number	Diff line number	Diff line change
`@@ -949,7 +949,8 @@ private void EnsureReadonlyBackgroundColor(bool value)`
`949`	`949`	`{`
`950`	`950`	`// If we have no specifically defined back color, we set the back color in case we're in dark mode.`
`951`	`951`	`if (Application.IsDarkModeEnabled`
`952`		`- && DarkModeRequestState is true)`
	`952`	`+ && DarkModeRequestState is true`
	`953`	`+ && !ShouldSerializeBackColor())`
`953`	`954`	`{`
`954`	`955`	`base.BackColor = value ? SystemColors.ControlLight : SystemColors.Window;`
`955`	`956`	`Invalidate();`