直接上代码：

TestMenuService.MenuServiceCSClient tesClient = new TestMenuService.MenuServiceCSClient();            var client = tesClient.GetType()                .GetMethod("GetMenuID",                    BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.IgnoreCase | BindingFlags.Instance);            if (client != null)            {            var s=client.Invoke(tesClient, new object[] {
   "5","3"});                if (s != null)                {                    Console.Write(s.ToString());                }            }

 感谢群友的指点