Version: 2021.3
Language : English
Use managed UWP plug-ins
Author native UWP plug-ins

Call and implement native UWP plug-ins

To call and implement native Universal Windows Platform (UWP) plug-insA set of code created outside of Unity that creates functionality in Unity. There are two kinds of plug-ins you can use in Unity: Managed plug-ins (managed .NET assemblies created with tools like Visual Studio) and Native plug-ins (platform-specific native code libraries). More info
See in Glossary
, you need to know how to create native plug-ins for Unity. For more information about native plug-ins and their uses, refer to Native plug-insA platform-specific native code library that is created outside of Unity for use in Unity. Allows you can access features like OS calls and third-party code libraries that would otherwise not be available to Unity. More info
See in Glossary
.

IL2CPP scripting backendA framework that powers scripting in Unity. Unity supports three different scripting backends depending on target platform: Mono, .NET and IL2CPP. Universal Windows Platform, however, supports only two: .NET and IL2CPP. More info
See in Glossary
supports the P/Invoke mechanism for native plug-ins. This means that you can call into native plug-ins directly from your C# code. To do this, you specify the native function prototype and then call it.

The following examples show you how to implement a native plug-in and call it from a C# script.

  1. Create a new .cpp file in your Unity project and insert the following native plug-in code:

        extern "C" __declspec(dllexport)
        int __stdcall CountLettersInString(wchar_t* str)
        {
            int length = 0;
            while (*str++ != nullptr)
                length++;
            return length;
        }
    
  2. Create a new C# script and replace its contents with the following code:

    [DllImport("MyPlugin.dll")]
        private static extern int CountLettersInString([MarshalAs(UnmanagedType.LPWStr)]string str);
        
        private void Start()
        {
            Debug.Log(CountLettersInString("Hello, native plug-in!"));
        }
    
  3. Add the component to a GameObjectThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
    See in Glossary
    in your sceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
    See in Glossary
    and enter Play mode. The console will print 22.

    using UnityEngine;
    public class ExamplePlugin : MonoBehaviour
    {
        [DllImport("MyPlugin.dll")]
        private static extern int CountLettersInString([MarshalAs(UnmanagedType.LPWStr)]string str);
        
        private void Start()
        {
            Debug.Log(CountLettersInString("Hello, native plug-in!"));
        }
    }
    

Additional resources

Use managed UWP plug-ins
Author native UWP plug-ins