public T Api <T>(string name) where T : YunpianApi
        {
            YunpianApi api = null;

            switch (name)
            {
            case ShortUrlApi.ApiName:
                api = new ShortUrlApi();
                break;

            case SignApi.ApiName:
                api = new SignApi();
                break;

            case SmsApi.ApiName:
                api = new SmsApi();
                break;

            case TplApi.ApiName:
                api = new TplApi();
                break;

            case UserApi.ApiName:
                api = new UserApi();
                break;

            case VideoSmsApi.ApiName:
                api = new VideoSmsApi();
                break;

            case VoiceApi.ApiName:
                api = new VoiceApi();
                break;
            }

            api?.Init(_clnt);

            return(api as T);
        }
 public void Init()
 {
     instance = new VoiceApi();
 }