> For the complete documentation index, see [llms.txt](https://docs.yarnspinner.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.yarnspinner.dev/2.4/api/csharp/yarn.unity/yarn.unity.actions/yarn.unity.actions.addcommandhandler-18.md).

# AddCommandHandler(string,Action\<T1, T2, T3, T4>)

Method in [Actions](/2.4/api/csharp/yarn.unity/yarn.unity.actions.md)

## Summary

```csharp
public void AddCommandHandler<T1, T2, T3, T4>(string commandName, Action<T1, T2, T3, T4> handler);
```

## Parameters

| Name                                    | Description |
| --------------------------------------- | ----------- |
| `string` commandName                    |             |
| `System.Action<T1, T2, T3, T4>` handler |             |