🪟 Glass.Message

The modern MessageBox replacement for .NET WinForms — Windows 11 ready, zero migration cost.

Mica & Acrylic backdrops · automatic dark/light theming · fluent builder API · async/await dialogs · inline text & password inputs · activity-aware live progress bars · toast notifications · per-monitor DPI · full RTL support.

NuGet Downloads .NET License

Glass.Message feature gallery — modern Windows 11 styled WinForms dialog

Why Glass.Message?

System.Windows.Forms.MessageBox hasn’t changed since Windows XP. It ignores dark mode, ignores your monitor’s DPI, can’t be awaited, and looks out of place on Windows 10/11. Glass.Message replaces it with a single type-name change — the Show(...) overloads are 100% signature-compatible and still return DialogResult.

// Before — flat grey dialog, blocks the thread, ignores dark mode
MessageBox.Show("Save failed. The file is in use by another process.",
    "Save Error", MessageBoxButtons.RetryCancel, MessageBoxIcon.Error);

// After — same one-liner, now modern, themed, DPI-aware, animated
GlassMessage.Show("Save failed. The file is in use by another process.",
    "Save Error", MessageBoxIcon.Error);

No new dependencies. No additional configuration. Works on .NET Framework 4.8.1 and .NET 8 / 9 / 10.

🆕 What’s new in v1.0.6

A quality, performance, and concurrency hardening maintenance release — no new features, no public API changes. Verified with real stress/concurrency tests and rendered DPI screenshots:

  • Improved concurrency behavior — GlassProgressController updates from background threads now coalesce instead of flooding the UI thread, verified under sustained multi-threaded load with no deadlocks or hangs.
  • Reduced rendering allocation pressure — toast notifications and the dialog’s close-button/countdown-ring no longer allocate new GDI+ objects on every repaint or animation frame; they’re built once and reused.
  • Improved resource management — GDI/USER handle counts verified stable across hundreds of dialog/toast create-and-dispose cycles.
  • DPI / rendering polish — dialog rescaling verified clean at 100–200% DPI from actual rendered output, with no cropping or visual artifacts.
  • Reliability — verified no stale toast state under rapid/simultaneous toast creation and dismissal, and no corruption when a DPI change occurs while progress updates and an open toast are concurrently active.

Full technical details: CHANGELOG.md.

Install

dotnet add package Glass.Message

Feature comparison

Capability MessageBox Glass.Message
Dark / light mode ✗ ✓ auto-detect
Windows 11 Mica backdrop ✗ ✓
Windows 10 Acrylic blur ✗ ✓
Rounded corners (DWM) ✗ ✓
Per-monitor DPI scaling ✗ ✓
async / await support ✗ ✓
CancellationToken support ✗ ✓
Open/close animations ✗ ✓ Fade, Slide, Scale
Inline text / password input ✗ ✓
Inline drop-down input ✗ ✓
Live progress bar ✗ ✓ determinate + marquee
Activity-aware progress animation ✗ ✓ upload / download / sync / compress / …
Checkbox (“don’t show again”) ✗ ✓
Expandable detail panel ✗ ✓
Toast notifications ✗ ✓ 6 positions, multi-monitor
Custom button labels ✗ ✓
Custom themes ✗ ✓
High contrast accessibility system only ✓ dedicated preset
Right-to-left layout ✗ ✓
Countdown auto-close ✗ ✓
Ctrl+C copies content ✗ ✓
.NET Framework 4.8.1 ✓ ✓
.NET 8 / 9 / 10 ✓ ✓

Quick start

using Glass;
using System.Windows.Forms;

// Optional — set once at startup (e.g. in Program.cs or Form_Load)
GlassMessage.UseRoundedCorners = true;                    // Windows 11 rounded corners
GlassMessage.DefaultTheme      = GlassTheme.AutoDetect(); // follow the OS light / dark theme
GlassMessage.PlaySystemSounds  = true;                    // match classic MessageBox behaviour

// Drop-in replacement (same signature, same DialogResult)
DialogResult result = GlassMessage.Show(
    "Your changes have been saved.", "Success", MessageBoxIcon.Information);

Examples

Custom buttons + fluent builder

var r = GlassMessage.Create("Annual_Report_Q4.xlsx has unsaved changes.")
    .Title("Unsaved Changes")
    .Icon(MessageBoxIcon.Warning)
    .Buttons("Save", "Don't Save", "Cancel")
    .Show();

Text / password input

// Text input with a checkbox
var r = GlassMessage.Create("Enter a new name for this folder.")
    .Title("Rename")
    .InputText("Folder name", "Client Projects")
    .CheckBox("Apply to sub-folders")
    .Buttons("Rename", "Cancel")
    .ShowEx();

if (r.Button == DialogResult.OK)
    RenameFolder(r.InputText, applyRecursive: r.CheckBoxChecked);

// Password input (masked, with reveal-eye toggle and Caps Lock hint)
var r = GlassMessage.Create("Enter your vault password to continue.")
    .Title("Authentication Required")
    .Icon(MessageBoxIcon.Shield)
    .InputPassword("Password")
    .Buttons("Unlock", "Cancel")
    .ShowEx();

Async dialogs with CancellationToken

// Non-blocking — the UI stays responsive while the dialog is open
var choice = await GlassMessage.ShowAsync(
    "Push local changes to origin/main?", "Sync",
    MessageBoxIcon.Question, MessageBoxButtons.OKCancel);

// Cancellable from code — e.g. session timeout after 30 s
using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(30));
var result = await GlassMessage.Create("Confirm deployment to production?")
    .Title("Deploy")
    .Icon(MessageBoxIcon.Warning)
    .Buttons("Deploy Now", "Cancel")
    .ShowAsync(cts.Token);

Live progress dialog (activity-aware)

The bar can animate to match the operation — Upload, Download, Sync, Compress, and more — and you can switch the activity live as the work moves between phases:

var ctrl = GlassMessage.Create("Uploading files to cloud storage…")
    .Title("Upload")
    .Progress(0, 100)
    .ProgressActivity(GlassProgressActivity.Upload)   // glowing packets flow →
    .Buttons("Cancel")
    .ShowProgress();

for (int i = 0; i <= 100; i += 10)
{
    if (ctrl.WasCanceledByUser) break;
    ctrl.SetValue(i);
    ctrl.SetMessage($"Uploading file {i / 10 + 1} of 10…");
    await Task.Delay(500);
}
ctrl.Complete();
await ctrl.Completion;

Toast notifications

// Fire-and-forget, bottom-right corner, auto-dismiss after 4 s
GlassToast.Show("Invoice #1042 saved to SharePoint.", "Upload Complete",
    MessageBoxIcon.Information);

// Awaitable toast — continues after the notification disappears
await GlassToast.ShowAsync(new GlassToastOptions
{
    Title     = "Build finished",
    Message   = "Release x64 completed in 4.2 s.",
    Icon      = MessageBoxIcon.None,
    Position  = ToastPosition.TopRight,
    DurationMs = 6_000,
    OnClick   = () => OpenBuildLog(),
});

Fluent builder API — custom inputs, checkboxes, progress, themes

Password input dialog with reveal-eye button and Caps Lock hint

Activity-aware progress bar animating a download flow

Theming

Five built-in presets — pick one or build your own:

Preset Description
GlassTheme.Default Dark blue (ships as the default)
GlassTheme.Light Bright palette for light-mode apps
GlassTheme.Mica Neutral, tuned for Windows 11 Mica backdrop
GlassTheme.HighContrast Full Windows system-colour accessibility preset
GlassTheme.WindowsClassic Square, opaque — matches traditional Windows chrome
GlassTheme.AutoDetect() Chooses Dark / Light / HighContrast at runtime

Target frameworks & platforms

Framework Notes
.NET Framework 4.8.1 Full support, ships explicit WinForms references
.NET 8.0-windows LTS
.NET 9.0-windows Current
.NET 10.0-windows Preview

AnyCPU — runs in both x86 and x64 processes.
Windows-only (WinForms). No third-party runtime dependencies.

Documentation & links

  • 📖 Full docs, gallery & API reference: https://github.com/gcfernando/glass
  • 📜 Changelog: https://github.com/gcfernando/glass/blob/main/CHANGELOG.md
  • ⬇️ Releases & pre-built binaries: https://github.com/gcfernando/glass/releases
  • 🐛 Issues & feature requests: https://github.com/gcfernando/glass/issues

MIT Licensed · © 2026 Gehan Fernando
Keywords: WinForms MessageBox replacement, Windows Forms modern dialog, dark mode dialog .NET, Windows 11 Mica dialog, Acrylic WinForms, async MessageBox C#, WinForms toast notification, DPI-aware dialog, WinForms progress dialog, WinForms input dialog, WinForms password dialog, themed dialog WinForms, GlassMessage, Glass.Message

Read all Glass.Message guides online · Project overview · All developer projects