public string BuildUri( string apiKey, string baseURL, string name, string stringParam, string uriExt) { var configuration = new ClientConfiguration { ApiDataSources = Enumerable .Range(0, 1) .Select(s => new ApiDataSource { Name = "Bar", ApiKey = apiKey, BaseURL = baseURL, EndPoints = new[] { new ApiEndPoint { Name = name, Parameters = stringParam.Split(','), UriExtension = uriExt } } }).ToDictionary(k => k.Name, v => v) }; var result = configuration.BuildUri("Bar", "Test", "R1", "R2").ToString(); return(result); }