WinControls

Lightweight dark mode and high-DPI theming for Windows Forms that augments the standard controls instead of replacing them.

Most WinForms theming libraries (Krypton, ReaLTaiizor, MaterialSkin, Guna) give you a whole new set of custom controls you must rebuild your UI around. WinControls takes the opposite approach: keep your existing standard controls, and recolor them in place. Drop it into an existing app and get a modern light/dark look with a couple of lines.

Targets .NET Framework 4.6.2 and .NET 8 (Windows) from a single package.

What you get

• Native dark title bar via the Desktop Window Manager (DwmSetWindowAttribute), Windows 10 1809+ and Windows 11. A safe no-op on older systems.
• Recursive control-tree recoloring for the standard controls: Form, Button, TextBox, ComboBox, ListBox, CheckBox, RadioButton, Label, LinkLabel, DataGridView, ListView, TreeView, and common containers.
• OS theme following: resolve ThemeMode.System from the user's Windows app theme preference.
• No custom control types: nothing to rebuild your forms around.

Install

dotnet add package WinControls

Quick start

Theme a form in its constructor:

using WinControls.Theming;

public partial class MainForm : Form
{
    public MainForm()
    {
        InitializeComponent();
        ThemeManager.Apply(this, ThemeMode.System); // dark title bar + recolor, follows OS
    }
}

That's it. ThemeManager.Apply:

1. Resolves the palette (System follows the OS; Dark/Light are explicit).
2. Sets the native title bar light/dark via DWM.
3. Recolors the entire control tree.

Switching themes at runtime

private void btnDark_Click(object sender, EventArgs e)
    => ThemeManager.Apply(this, ThemeMode.Dark);

Following live OS theme changes

Microsoft.Win32.SystemEvents.UserPreferenceChanged += (_, _) =>
    ThemeManager.Refresh(this, ThemeMode.System);

Custom palette

var brand = new ThemePalette(
    isDark: true,
    windowBackground: Color.FromArgb(18, 18, 24),
    surface:          Color.FromArgb(28, 28, 38),
    foreground:       Color.White,
    mutedForeground:  Color.Gray,
    border:           Color.FromArgb(50, 50, 64),
    accent:           Color.MediumPurple,
    accentForeground: Color.White,
    controlBackground:Color.FromArgb(34, 34, 46),
    controlBorder:    Color.FromArgb(70, 70, 90),
    selectionBackground: Color.MediumPurple,
    selectionForeground: Color.White);

ThemeManager.ApplyPalette(this, brand);

API overview

Type	Purpose
ThemeManager	Entry point: Apply(form, mode), ApplyPalette(form, palette), Refresh(...).
ThemePalette	Immutable color set; built-in Dark / Light.
ThemeMode	Light, Dark, or System.
ThemeApplier	Recolors a control tree in place (use directly to theme a sub-panel).
SystemTheme	Reads the OS app theme preference; Resolve(mode) -> palette.
WindowChrome	Low-level DWM dark title bar (Apply(form, dark), SetDarkTitleBar(handle, dark)).

Design notes

• Augment, not replace. Standard controls are recolored via their properties; Buttons use FlatStyle.Flat, DataGridView uses EnableHeadersVisualStyles = false. Unknown/third-party controls get container-level colors and are otherwise untouched.
• Pattern-match ordering. Derived control types (e.g. LinkLabel : Label) are matched before their bases so each gets the right treatment.
• Graceful degradation. The dark title bar is best-effort: on Windows versions that don't support the DWM attribute, theming still recolors the client area.

Build & test

dotnet build
dotnet test

Multi-targets net462 and net8.0-windows. The 11 tests cover palette definitions, OS-preference interpretation, and ThemeApplier recoloring real control trees.

Sample

samples/WinControls.Demo is a form full of standard controls with a Light/Dark/ System switcher, showing in-place theming and the native title bar.

Roadmap

• Owner-drawn scrollbars and a dark context-menu renderer.
• Opt-in flat tab and toolstrip renderers.

License

MIT. See LICENSE.