public override void Abort()
        {
            //如果已经完成或出错,则无效。
            if (m_State == State.Error || m_State == State.Completed)
            {
                return;
            }

            base.Abort();

            //清除未完成的loader
            if (m_DependencyLoaders != null && m_DependencyLoaders.Count > 0)
            {
                for (int i = 0; i < m_DependencyLoaders.Count; ++i)
                {
                    AssetBundleAsyncLoader depLoader = m_DependencyLoaders[i];
                    depLoader.onAssetBundleLoaded -= OnDependencyLoaded;
                    depLoader.onBeforeComplete    -= OnBeforeDependencyComplete;
                    depLoader.onComplete          -= OnDependencyComplete;
                    depLoader.DecreaseLoadingRequest();
                }
                m_DependencyLoaders.Clear();
            }

            //清除已经加载的AssetBundle
            ClearDependencies();

            //清除本身资源
            if (m_Request != null)
            {
                m_Request.onComplete -= OnBundleRequestComplete;
                m_Request             = null;
            }

            //执行一次加载完成
            DoLoadComplete();
        }