C++函数定义转C#问题
这是C++头文件的函数定义，那转成C#该是如何呢？特别是第二个参数，转了半天都有Error

C++
libmosq_EXPORT void mosquitto_connect_callback_set(struct mosquitto *mosq, void (*on_connect)(struct mosquitto *, void *, int));

C#（我自己转的，不对）
private static extern void mosquitto_message_callback_set(IntPtr mosq, IntPtr(on_message)(IntPtr mosquitto, IntPtr, IntPtr mosquitto_message));

求教大师 c++ c#
[解决办法]
函数指针，你应该定义成委托：

void delegate on_connectDelegate(mosquitto mosq, IntPtr p, int i);

void mosquitto_connect_callback_set(mosquitto mosq, on_connectDelegate);
[解决办法]
用Delegate.下面的例子来自msdn:
C++
typedef void (__stdcall *PFN_MYCALLBACK)();
int __stdcall MyFunction(PFN_ MYCALLBACK callback);

C#
public delegate void MyCallback();
[DllImport("MYDLL.DLL")]
public static extern void MyFunction(MyCallback callback);

msdn链接：http://msdn.microsoft.com/en-us/library/aa288468(v=vs.71).aspx