Getting Started

Getting Started

This guide will help you install Dapplo.Windows and start using its packages.

Prerequisites

• Windows operating system
• .NET Framework 4.6.2+ or .NET Core 3.1+ / .NET 5+
• Visual Studio 2019+ or any compatible IDE

Installation

Dapplo.Windows is distributed as multiple NuGet packages. Install only the packages you need:

# Window management and WinEvent hooks
Install-Package Dapplo.Windows

# Reactive clipboard monitoring and manipulation
Install-Package Dapplo.Windows.Clipboard

# DPI awareness and scaling
Install-Package Dapplo.Windows.Dpi

# Low-level keyboard and mouse hooks, input generation
Install-Package Dapplo.Windows.Input

Or with the .NET CLI:

dotnet add package Dapplo.Windows
dotnet add package Dapplo.Windows.Clipboard
dotnet add package Dapplo.Windows.Dpi
dotnet add package Dapplo.Windows.Input

Your First Window Query

Get information about the currently active window:

using Dapplo.Windows.Desktop;
using Dapplo.Windows.User32;

// Get the foreground window
var handle = User32Api.GetForegroundWindow();
var window = InteropWindow.FromHandle(handle);
window.Fill();

Console.WriteLine($"Title:   {window.Caption}");
Console.WriteLine($"Class:   {window.Classname}");
Console.WriteLine($"Bounds:  {window.Bounds}");
Console.WriteLine($"Visible: {window.IsVisible()}");

Your First Clipboard Monitor

Subscribe to clipboard changes reactively:

using Dapplo.Windows.Clipboard;
using System.Reactive.Linq;

var subscription = ClipboardNative.OnUpdate
    .Where(info => info.Formats.Contains("Text"))
    .Subscribe(info =>
    {
        using var clipboard = ClipboardNative.Access();
        Console.WriteLine($"New clipboard text: {clipboard.GetAsString()}");
    });

// Keep the application alive (e.g., Console.ReadLine()) then clean up:
subscription.Dispose();

Your First Keyboard Hook

React to keyboard input system-wide:

using Dapplo.Windows.Input.Keyboard;
using System.Reactive.Linq;

using var keyboardHook = KeyboardHook.Create();

var subscription = keyboardHook.KeyboardEvents
    .Where(e => e.Key == VirtualKeyCode.Snapshot && e.IsDown)
    .Subscribe(_ => Console.WriteLine("Print Screen pressed!"));

Console.ReadLine();

Resource Management

Always dispose subscriptions and hooks when you are done:

// IDisposable-based hooks and subscriptions
using var keyboardHook = KeyboardHook.Create();
using var subscription = keyboardHook.KeyboardEvents.Subscribe(...);

// Clipboard access uses a lock — always release it
using (var clipboard = ClipboardNative.Access())
{
    var text = clipboard.GetAsString();
}

Threading

Many Windows APIs must be called from the correct thread. Use ObserveOn to marshal events to the UI thread when needed:

using System.Reactive.Concurrency;

ClipboardNative.OnUpdate
    .ObserveOn(SynchronizationContext.Current)   // switch to UI thread
    .Subscribe(info => labelStatus.Text = "Clipboard changed");

Next Steps

Topic	What you will learn
Window-Management	Enumerate, query, and manipulate windows
Clipboard	Full clipboard API — read, write, formats, Cloud Clipboard
Input-Handling	Keyboard/mouse hooks and input generation
DPI-Awareness	Build crisp applications on high-DPI displays
Restart-Manager	Register for automatic restart with Windows
Icon-Creation	Extract and convert icons
Common-Scenarios	Real-world recipes using multiple packages