Learn .NET - Desktop & Cross-platform Apps

#Introduction

.NET is not only for servers — it also builds desktop and mobile applications. Episode 21 explores that world: .NET MAUI for cross-platform, WPF and WinForms for Windows, and Blazor, which brings your web skills to desktop and mobile.

The big theme is one skill, many surfaces. With C# knowledge, you can build native UIs on various platforms. This episode gives you a technology map so you can pick the right one for each need.

#.NET MAUI for Cross-Platform

#One Codebase, Many Platforms

.NET MAUI targets Windows, macOS, iOS, and Android from a single project. Create a project:

dotnet new maui -n MyApp
dotnet build -t:Run -f net9.0-android

dotnet new maui -n MyApp creates a project with per-platform targets in .csproj. A single UI codebase is written with XAML, while platform-specific features can be accessed through components like Microsoft.Maui.Platform.

#The MAUI Project Structure

A MAUI project contains MauiProgram.cs as the entry point and separate platform folders:

public static class MauiProgram
{
    public static MauiApp CreateMauiApp()
    {
        var builder = MauiApp.CreateBuilder();
        builder.Services.AddSingleton<MainPage>();
        return builder.Build();
    }
}

MauiApp.CreateBuilder uses the same pattern as the Generic Host — DI and configuration work just like in episode 8. The page XAML defines the UI declaratively, and MainPage is resolved from the container.

#WPF and WinForms for Windows

#WPF for Modern Windows UI

WPF is the Windows UI framework with XAML and rich visual composition — the choice for complex Windows desktop applications. Create a project:

dotnet new wpf -n DesktopApp
dotnet run --project DesktopApp

dotnet new wpf -n DesktopApp produces a project with MainWindow.xaml. WPF suits Windows business applications with complex layouts, data binding, and strong styling.

#WinForms for Rapid Productivity

WinForms offers fast drag-and-drop visual development — ideal for internal tools and simple applications that prioritize development speed. The choice is simple: WinForms for simple, fast needs; WPF for applications that require a modern, rich UI.

#Blazor WebAssembly and Blazor Server

#Blazor for Interactive Web UI

Blazor brings C# to the browser. Two hosting models:

• Blazor WebAssembly: code runs in the browser via WebAssembly.
• Blazor Server: code runs on the server, the UI is updated via SignalR.

dotnet new blazor -n InteractiveWeb
dotnet run --project InteractiveWeb

dotnet new blazor produces an application with .razor components that mix markup and C#. The same components can also run on desktop via Blazor Hybrid — combining web UI with the native power of MAUI.

#Razor Components

One component handles both view and logic:

@code {
    private int jumlah = 0;
 
    private void Tambah()
    {
        jumlah++;
    }
}
 
<button @onclick="Tambah">Klik: @jumlah</button>

@code holds the C# logic, and the markup uses directives like @onclick. Components are reusable and can be shared across applications — from server to mobile.

#Packaging, Distribution, and Deployment

#Publishing Applications

Each technology has its own way to publish:

dotnet publish -c Release -r win-x64

For WPF, dotnet publish -r win-x64 produces a folder that can be packaged into an installer (MSIX or MSI). MAUI uses the dotnet publish -f net9.0-android command to produce APK/AAB, and Xcode/App Store for iOS.

#Distribution Channels

• Windows: MSIX, MSI, or ClickOnce.
• Android: Google Play, sideloaded APK.
• iOS: App Store with Apple signing.
• Internal desktop: zip files or corporate installers.

Each channel has its own signing and certificate requirements. Plan distribution from the start because publishing to stores involves a verification process.

#Desktop and Mobile Practice Summary

• Use MAUI for cross-platform from a single codebase.
• WPF for modern Windows UI; WinForms for rapid development.
• Blazor brings C# to web, desktop, and mobile.
• Publish with specific runtimes and platform targets.
• Plan signing and distribution channels from the start.

#Closing

Key takeaways:

• .NET MAUI targets Windows, macOS, iOS, and Android.
• WPF and WinForms are the two paths for Windows desktop applications.
• Blazor WebAssembly runs in the browser; Blazor Server on the server.
• Razor components can be shared across platforms.
• Publishing requires the right runtime identifier and signing.
• Distribution channels determine the packaging process and certificates.

In the next episode 22 we will discuss stable modern features and future trends — minimal APIs, source generators, hot reload, and AOT, the release roadmap and .NET LTS strategy, cloud, microservices, AI/ML, and edge ecosystem trends, and strategies for keeping your .NET skills relevant.