C#使用MonoPInvokeCallback，让C直接回调C#函数

char* TestMakeCString(NSString *str) {

    const char* string = [str UTF8String];

    if (string == NULL) {

        return NULL;

    }

    char* res = (char*)malloc(strlen(string) + );

    strcpy(res, string);

    return res;

}

extern "C"{

    typedef void (*TestCallback)(const char*eventName);

    TestCallback _myCallback;

    void _TestInit(TestCallback callback){

        _myCallback=callback;

    }

}

@implementation Test

-(void) test{

    _myCallback(TestMakeCString(@"complete"));

}

@end

using System.Runtime.InteropServices;

public class Test{

    public delegate void EventHandler(string eventName, string msg);

    public event EventHandler callbackHandler;

    internal delegate void TestCallBack(string eventName);

    [DllImport("__Internal")]

    private static extern void _TestInit(TestCallBack callback);

    [MonoPInvokeCallback(typeof(TestCallBack))]

    public static void onCallBack(string eventName){

        if(eventName=="complete"){

            //do something

            if(callbackHandler!=null)callbackHandler(eventName,"HIJK");

        }

    }

     public static Test _instance;

     public static Test getInstance(){

     　　if(_instance==null){

         　　_instance=new Test();

     　　}

     　　return _instance;

      }

    //初始接口

    public void init(){

        _TestInit(onCallBack);

    }

}

Test test=Test.getInstance()

test.init();

test.callbackHandler+=handler;

void handler(string eventName,string msg){

　　//do something

}