public static UnityHttpClient GetAssetBundle(string url, uint crc, Action <UnityHttpClient, UnityHttpResponse> resultCallback = null, Action <UnityHttpClient, string> errorCallback = null)
        {
            UnityHttpRequest req    = new UnityHttpRequest(url, crc);
            UnityHttpClient  client = new UnityHttpClient(resultCallback, errorCallback);

            client.SendRequest(req);
            return(client);
        }
        public static UnityHttpClient GetTexture(string url, bool readable = false, Action <UnityHttpClient, UnityHttpResponse> resultCallback = null, Action <UnityHttpClient, string> errorCallback = null)
        {
            UnityHttpRequest req    = new UnityHttpRequest(url, readable);
            UnityHttpClient  client = new UnityHttpClient(resultCallback, errorCallback);

            client.SendRequest(req);
            return(client);
        }
        public static UnityHttpClient GetAudioClip(string url, AudioType audioType, Action <UnityHttpClient, UnityHttpResponse> resultCallback = null, Action <UnityHttpClient, string> errorCallback = null)
        {
            UnityHttpRequest req    = new UnityHttpRequest(url, audioType);
            UnityHttpClient  client = new UnityHttpClient(resultCallback, errorCallback);

            client.SendRequest(req);
            return(client);
        }
        public void SendRequest(UnityHttpRequest request)
        {
            if (disposed)
            {
                throw new ObjectDisposedException("unityWebRequest");
            }

            this.request = request;
            SetRequestHeaders();
            unityWebRequest.url    = request.RequestUriText;
            unityWebRequest.method = request.MethodText;

            if (request.CanDownloadData)
            {
                unityWebRequest.downloadHandler = request.DownloadHandler;
            }
            else
            {
                unityWebRequest.downloadHandler = null;
            }

            Observable.FromCoroutine(SendRequest).Subscribe();
        }