62 lines
2.8 KiB
Markdown
62 lines
2.8 KiB
Markdown
# The Command Service
|
|
|
|
[Discord.Commands](xref:Discord.Commands) provides an Attribute-based Command Parser.
|
|
|
|
### Setup
|
|
|
|
To use Commands, you must create a [Commands Service](xref:Discord.Commands.CommandService) and a Command Handler.
|
|
|
|
Included below is a very bare-bones Command Handler. You can extend your Command Handler as much as you like, however the below is the bare minimum.
|
|
|
|
[!code-csharp[Barebones Command Handler](samples/command_handler.cs)]
|
|
|
|
## Modules
|
|
|
|
Modules serve as a host for commands you create.
|
|
|
|
To create a module, create a class that you will place commands in. Flag this class with the `[Module]` attribute. You may optionally pass in a string to the `Module` attribute to set a prefix for all of the commands inside the module.
|
|
|
|
### Example Module
|
|
|
|
[!code-csharp[Modules](samples/module.cs)]
|
|
|
|
#### Loading Modules Automatically
|
|
|
|
The Command Service can automatically discover all classes in an Assembly that are flagged with the `Module` attribute, and load them.
|
|
|
|
To have a module opt-out of auto-loading, pass `autoload: false` in the Module attribute.
|
|
|
|
Invoke [CommandService.LoadAssembly](xref:Discord.Commands.CommandService#Discord_Commands_CommandService_LoadAssembly) to discover modules and install them.
|
|
|
|
#### Loading Modules Manually
|
|
|
|
To manually load a module, invoke [CommandService.Load](xref:Discord.Commands.CommandService#Discord_Commands_CommandService_Load), and pass in an instance of your module.
|
|
|
|
### Module Constructors
|
|
|
|
When automatically loading modules, you are limited in your constructor. Using a constructor that accepts _no arguments_, or a constructor that accepts a @Discord.Commands.CommandService will always work.
|
|
|
|
Alternatively, you can use an @Discord.Commands.IDependencyMap, as shown below.
|
|
|
|
## Dependency Injection
|
|
|
|
The Commands Service includes a very basic implementation of Dependency Injection that allows you to have completely custom constructors, within certain limitations.
|
|
|
|
### Setup
|
|
|
|
First, you need to create an @Discord.Commands.IDependencyMap . The library includes @Discord.Commands.DependencyMap to help with this, however you may create your own IDependencyMap if you wish.
|
|
|
|
Next, add the dependencies your modules will use to the map.
|
|
|
|
Finally, pass the map into the `LoadAssembly` method. Your modules will automatically be loaded with this dependency map.
|
|
|
|
[!code-csharp[DependencyMap Setup](samples/dependency_map_setup.cs)]
|
|
|
|
### Usage in Modules
|
|
|
|
In the constructor of your module, any parameters will be filled in by the @Discord.Commands.IDependencyMap you pass into `LoadAssembly`.
|
|
|
|
>[!NOTE]
|
|
>If you accept `CommandService` or `IDependencyMap` as a parameter in your constructor, these parameters will be filled by the CommandService the module was loaded from, and the DependencyMap passed into it, respectively.
|
|
|
|
[!code-csharp[DependencyMap in Modules](samples/dependency_module.cs)] |