Introduction

.NET Generic Host
Bare Bones

Adding commands with the .NET Generic Host is very easy. Use AddCommands(IServiceCollection) to add the command service to your host builder. Then, use AddCommand to add a command using the minimal APIs way and/or use AddModules(IHost, Assembly) to add command modules from an assembly.

using Microsoft.Extensions.Hosting;

using NetCord.Hosting.Gateway;
using NetCord.Hosting.Services;
using NetCord.Hosting.Services.Commands;

var builder = Host.CreateApplicationBuilder(args);

builder.Services
    .AddDiscordGateway()
    .AddCommands();

var host = builder.Build();

// Add a command using minimal APIs
host.AddCommand(["pong"], () => "Ping!");

// Add commands from modules
host.AddModules(typeof(Program).Assembly);

await host.RunAsync();

Specifying a prefix

You can specify a prefix in the configuration. You can for example use appsettings.json file. It should look like this:

{
  "Discord": {
    "Prefix": "!"
    // You can also specify multiple prefixes using 'Prefixes'
    // "Prefixes": [ "!", "?" ]
  }
}

First, add the following lines to the using section.

using NetCord.Services;
using NetCord.Services.Commands;

Now, it's time to create CommandService<TContext> instance and add commands to it.

// Create the command service
CommandService<CommandContext> commandService = new();

// Add commands using minimal APIs
commandService.AddCommand(new CommandBuilder(["ping"], () => "Pong!"));

// Add commands from modules
commandService.AddModules(typeof(Program).Assembly);

We can add a command handler now.

// Add the handler to handle commands
client.MessageCreate += async message =>
{
    // Check if the message is a command (starts with '!' and is not from a bot)
    if (!message.Content.StartsWith('!') || message.Author.IsBot)
        return;

    // Execute the command
    var result = await commandService.ExecuteAsync(prefixLength: 1, new CommandContext(message, client));

    // Check if the execution failed
    if (result is not IFailResult failResult)
        return;

    // Return the error message to the user if the execution failed
    try
    {
        await message.ReplyAsync(failResult.Message);
    }
    catch
    {
    }
};

The Final Product

Program.cs

using NetCord;
using NetCord.Gateway;
using NetCord.Logging;
using NetCord.Services;
using NetCord.Services.Commands;

GatewayClient client = new(new BotToken("Token from Discord Developer Portal"), new GatewayClientConfiguration
{
    Intents = GatewayIntents.GuildMessages | GatewayIntents.DirectMessages | GatewayIntents.MessageContent,
    Logger = new ConsoleLogger(),
});

// Create the command service
CommandService<CommandContext> commandService = new();

// Add commands using minimal APIs
commandService.AddCommand(new CommandBuilder(["ping"], () => "Pong!"));

// Add commands from modules
commandService.AddModules(typeof(Program).Assembly);

// Add the handler to handle commands
client.MessageCreate += async message =>
{
    // Check if the message is a command (starts with '!' and is not from a bot)
    if (!message.Content.StartsWith('!') || message.Author.IsBot)
        return;

    // Execute the command
    var result = await commandService.ExecuteAsync(prefixLength: 1, new CommandContext(message, client));

    // Check if the execution failed
    if (result is not IFailResult failResult)
        return;

    // Return the error message to the user if the execution failed
    try
    {
        await message.ReplyAsync(failResult.Message);
    }
    catch
    {
    }
};

await client.StartAsync();
await Task.Delay(-1);

Example Module

using NetCord.Services.Commands;

namespace MyBot;

public class ExampleModule : CommandModule<CommandContext>
{
    [Command("ping")]
    public string Ping() => $"Pong! {Math.Round(Context.Client.Latency.TotalMilliseconds)} ms";
}

Table of Contents

Introduction

Specifying a prefix

Example Module