public void UnLoadRes(string path)
        {
            if (!AllResItems.ContainsKey(path))
            {
                return;
            }

            var refs = AllResItems[path].resRefs;

            for (int i = 0; i < refs.Count; i++)
            {
                if (refs[i].IsAlive)
                {
                    Debug.LogError("该资源还有引用--->" + path);
                    return;
                }
            }

            Resources.UnloadAsset(AllResItems[path].Res);
        }
        // 载入资源并带有一个弱引用
        public T LoadRes <T>(UnityEngine.Object resRef, string path) where T : UnityEngine.Object
        {
            if (AllResItems.ContainsKey(path))
            {
                if (resRef != null)
                {
                    AllResItems[path].AddRef(resRef);
                }
                return(AllResItems[path] as T);
            }

            T   tmp = Resources.Load <T>(path);
            var res = new ResItem();

            res.Res = tmp;
            if (resRef != null)
            {
                res.AddRef(resRef);
            }
            AllResItems[path] = res;
            return(tmp);
        }