Writing Code

Note

Make sure you have created a project. Once you have a project, you can start coding!

You should have a project that looks like this:

• CHANGELOG.md
• Config.Build.user.props.template
• Directory.Build.props
• Directory.Build.targets
• icon.png
• LICENSE
• YAPYAPMod.sln
• README.md
• Directorysrc

  • DirectoryYAPYAPMod

    • YAPYAPMod.csproj
    • Plugin.cs
    • thunderstore.toml

Tip

The Plugin.cs file contains your code while the csproj, props, and targets files are for build configuration. You can look inside all of the files and look for comments that explain what everything does.

Open the project in your IDE of choice where the .sln file is, and then open the Plugin.cs file. It should look something like this:

Plugin.cs

using BepInEx;
using BepInEx.Logging;

namespace YAPYAPMod;

// Here are some basic resources on code style and naming conventions to help
// you in your first CSharp plugin!
// https://learn.microsoft.com/en-us/dotnet/csharp/fundamentals/coding-style/coding-conventions
// https://learn.microsoft.com/en-us/dotnet/csharp/fundamentals/coding-style/identifier-names
// https://learn.microsoft.com/en-us/dotnet/standard/design-guidelines/names-of-namespaces

// This BepInAutoPlugin attribute comes from the Hamunii.BepInEx.AutoPlugin
// NuGet package, and it will generate the BepInPlugin attribute for you!
// For more info, see https://github.com/Hamunii/BepInEx.AutoPlugin
[BepInAutoPlugin]
public partial class Plugin : BaseUnityPlugin
{
    internal static ManualLogSource Log { get; private set; } = null!;

    private void Awake()
    {
        // BepInEx gives us a logger which we can use to log information.
        // See https://lethal.wiki/dev/fundamentals/logging
        Log = Logger;

        // BepInEx also gives us a config file for easy configuration.
        // See https://lethal.wiki/dev/intermediate/custom-configs

        // We can apply our hooks here.
        // See https://lethal.wiki/dev/fundamentals/patching-code

        // Log our awake here so we can see it in LogOutput.log file
        Log.LogInfo($"Plugin {Name} is loaded!");
    }
}

This is a very basic BepInEx 5 plugin. For more info, see BepInEx’s own documentation:

Creating a new plugin project—Plugin structure

You can also follow the links to learn more about each thing mentioned:

Logging: lethal.wiki

Custom Configs: lethal.wiki

Patching Code: lethal.wiki

For patching/hooking methods, you can use MonoMod or HarmonyX. See lethal.wiki for more in-depth introductions on using them.

Note

MonoDetour is also an option for hooking, but it’s in pre-release state and therefore is not fit for production usage yet. You can find its documentation at https://monodetour.github.io/

All of these libraries are compatible with each other as HarmonyX and MonoDetour simply use MonoMod.RuntimeDetour under the hood.

Writing Your First Hook

Currently we have nothing on this, but feel free to click the edit page button below to add content!

Useful BepInEx APIs Learn about useful BepInEx APIs you can use

Publishing Your Mod Upload your mod for everyone to download!