1.同步加载一个：

        public T LoadAsset<T>(string key, Action<T> callback = null)
        {
            var op = Addressables.LoadAssetAsync<T>(key);
            var t = op.WaitForCompletion();
            callback?.Invoke(t);
            Addressables.Release(op);
            return t;
        }

2.同步加载多个：

        public IList<T> LoadAssets<T>(string key, Action<T> callback = null)
        {
            var op = Addressables.LoadAssetsAsync<T>(key, ta => callback?.Invoke(ta));
            var t = op.WaitForCompletion();
            Addressables.Release(op);
            return t;
        }

3.异步加载一个：

        public async Task<T> LoadAssetAsync<T>(string key, Action<T> callback = null)
        {
            var t = await Addressables.LoadAssetAsync<T>(key).Task;
            callback?.Invoke(t);
            return t;
        }

4.异步加载：

public async Task LoadAllEffectObj()
{
    var loadedEffects = new List<GameObject>();

    int count = EFX.rows.Length;
    for (int i = 0; i < EFX.rows.Length; ++i)
    {
        var path = StringUtility.GetBuilder().Append(EFX.rows[i].respath).Append(EFX.rows[i].m枚举).Append(".prefab").ToString();
        LoadMgr.Instance.LoadAssetAsync<GameObject>(path,
            (x) =>
            {
                count--;
                if (x != null)
                {
                    Debug.Log("加载特效：" + path);
                    loadedEffects.Add(x);
                }
                else
                {
                    Debug.LogError("加载特效失败：" + path);
                }
            });
    }

    await Task.Run(() =>
    {
        while (count > 0)
        {
            //wait
        }
        return;
    });


    ObjectPool.PreloadedPrefab[] allPrefabs = new ObjectPool.PreloadedPrefab[loadedEffects.Count];
    for (int i = 0; i < loadedEffects.Count; i++)
    {
        ObjectPool.PreloadedPrefab preloadedPrefab = new ObjectPool.PreloadedPrefab(loadedEffects[i], 2) { };
        allPrefabs[i] = preloadedPrefab;
    }
    ObjectPool.Instance.AddPreloadPrefabs(allPrefabs);
}