Minecraft Launcher

Basic Usage

In .NET Framework, add the following code to maximize the download speed. This is not necessary in .NET Core.

System.Net.ServicePointManager.DefaultConnectionLimit = 256;

// initialize the launcher
var path = new MinecraftPath();
var launcher = new MinecraftLauncher(path);

// add event handlers
launcher.FileProgressChanged += (sender, args) =>
{
    Console.WriteLine($"Name: {args.Name}");
    Console.WriteLine($"Type: {args.EventType}");
    Console.WriteLine($"Total: {args.TotalTasks}");
    Console.WriteLine($"Progressed: {args.ProgressedTasks}");
};
launcher.ByteProgressChanged += (sender, args) =>
{
    Console.WriteLine($"{args.ProgressedBytes} bytes / {args.TotalBytes} bytes");
};

// get all versions
var versions = await launcher.GetAllVersionsAsync();
foreach (var v in versions)
{
    Console.WriteLine(v.GetVersionType());
    Console.WriteLine(v.Name);
}

// install and launch the game
await launcher.InstallAsync("1.20.6");
var process = await launcher.BuildProcessAsync("1.20.6", new MLaunchOption
{
    Session = MSession.CreateOfflineSession("Gamer123"),
    MaximumRamMb = 4096
});
process.Start();

Explaination

var path = new MinecraftPath();
var launcher = new MinecraftLauncher(path);

Create Minecraft directory structure and initialize launcher instance. You can change the path and directory structure. See Minecraft Path and MinecraftLauncherParameters

launcher.FileProgressChanged += (sender, args) =>
{
    Console.WriteLine($"Name: {args.Name}");
    Console.WriteLine($"Type: {args.EventType}");
    Console.WriteLine($"Total: {args.TotalTasks}");
    Console.WriteLine($"Progressed: {args.ProgressedTasks}");
};
launcher.ByteProgressChanged += (sender, args) =>
{
    Console.WriteLine($"{args.ProgressedBytes} bytes / {args.TotalBytes} bytes");
};

Add event handler. It prints download progress to console. See Event Handling

var versions = await launcher.GetAllVersionsAsync();
foreach (var v in versions)
{
    Console.WriteLine(v.Name);
}

Get all version and print its names. See Versions

await launcher.InstallAsync("1.20.4");
var process = await launcher.BuildProcessAsync("1.20.4", new MLaunchOption
{
    Session = MSession.CreateOfflineSession("Gamer123"),
    MaximumRamMb = 4096
});
process.Start();

Install the game and build the game process and return it. See Launch Options for more launch options.

More Methods

Get all files to launch the version

// by version name
IEnumerable<GameFile> files = await launcher.ExtractFiles("1.20.4", cancellationToken);

// by IVersion 
IVersion version = await launcher.GetVersionAsync("1.20.4", cancellationToken);
IEnumerable<GameFile> files = await launcher.ExtractFiles(version, cancellationToken);

Scan files and download any files that need to be downloaded

// report install progress to launcher.FileProgressChanged, launcher.ByteProgressChanged
await launcher.InstallAsync("1.20.4", cancellationToken); // by version name
await launcher.InstallAsync(version, cancellationToken); // by IVersion 

// report install progress to fileProgress, byteProgress
await launcher.InstallAsync("1.20.4", fileProgress, byteProgress, cancellationToken); // by version name 
await launcher.InstallAsync(version, fileProgress, byteProgress, cancellationToken); // by IVersion 

Build game process

// by version name
Process process = await launcher.BuildProcessAsync("1.20.4", new MLaunchOption(), cancellationTokene);

// by IVersion
IVersion version = await launcher.GetVersionAsync("1.20.4", cancellationToken);
Process process = launcher.BuildProcess(version, new MLaunchOption());

Get the Java path required to launch the version

IVersion version = await launcher.GetVersionAsync("1.20.4", cancellationToken);
string? javaPath = await launcher.GetJavaPath(version);

Get the path to the first installed Java

string? javaPath = await launcher.GetDefaultJavaPath();

API References

Methods

ValueTask InstallAndBuildProcessAsync(string versionName, MLaunchOption launchOption, CancellationToken cancellationToken = default)