[DllImport("ZKEM.dll", EntryPoint = "OnConnectedZkem_CB", CallingConvention = CallingConvention.Cdecl, CharSet = CharSet.Unicode)]
private static extern void OnConnectedZkem_CB(int index, int err, string User);
然后在你的C#代码里直接用:
OnConnectedZkem_CB(1,1,"")
就可以啊