c# - Unity - How to use c++ dll? -

i have ar application. created c++ dll using visual studio 2013. use dll in ar application below :

**in private members region :** [dllimport ("dllexample")] private static extern int func(int x, int y); .......  **in c# function :**  if (func((int)pos.x, (int)pos.y) == -1) {     ... } else {                   ... } 

my unity application works fine unity editor. build app android. when run on android device, doesn't work.

content of c++ dll :

// dllmain.cpp : defines entry point dll application. #include "stdafx.h" #include <opencv2\core\core.hpp> #include <opencv2\highgui\highgui.hpp> #include <opencv2\imgproc\imgproc.hpp>         #include <fstream> #include <iostream>  extern "c" __declspec(dllexport) int func(int x, int y);  bool apientry dllmain( hmodule hmodule,                    dword  ul_reason_for_call,                    lpvoid lpreserved                  ) { switch (ul_reason_for_call) { case dll_process_attach: case dll_thread_attach: case dll_thread_detach: case dll_process_detach:     break; } return true; }   __declspec(dllexport) int func(int x, int y) {    cv::rng rng(12345); cv::mat image0, image, gray, mask; int ffillmode = 1; int lodiff = 20, updiff = 20; int connectivity = 4; int iscolor = true; bool usemask = false; int newmaskval = 255;  return x; } 

in unity c# file, if remove call dll function, application works fine on android device .i use free unity version. how can use c++ dll on mobile device?

you need place dll file in in android plugin folder work. android plugin folder assets/plugins/android. create if doesnt exit.

edit: unity plugin not available in non pros according research. unity plugin supported in both free , pro unity 5. need update unity 5. here link of person made unity support plugin in unity free version.