public ApiController(string apiVersion, IndividualApiConfig apiConfig = null) { this.apiVersion = apiVersion; this._apiConfig = apiConfig; this.CheckState(); this.hostUrl = _apiConfig?.GetLiveUrl() ?? ApiConfig.GetLiveUrl(); if (_apiConfig?.IsSandbox() ?? ApiConfig.IsSandbox()) { this.hostUrl = _apiConfig?.GetSandboxUrl() ?? ApiConfig.GetSandboxUrl(); } }