public async Task ShouldConvertArrayToUri() { // arrange const string baseUrl = "http://localhost"; QueryString queryString = new QueryString(); var values = new int[] { 1, 2, 3 }; // act foreach (var v in values) { queryString.Add("key1", v.ToString()); } queryString.Add("key2", "value2"); Uri uri = await queryString.AsUriAsync(baseUrl); // assert Assert.NotNull(uri); Assert.True(uri.ToString() == "http://localhost/?key1=1&key1=2&key1=3&key2=value2"); }