Call and implement native UWP plug-ins

To call and implement native Universal Windows Platform (UWP) plug-ins, 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-ins.

IL2CPP scripting backend 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 GameObject in your scene 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!"));
       }
   }
   

その他の参考資料

• ネイティブプラグイン
• プラグインのインポートと設定
• Use P/invoke