C# (CSharp) SetList.FirstOrDefault示例

        public async Task <IActionResult> OnGet([FromQuery] string set)
        {
            var sets = await _scryfallApi.Sets.Get();

            SetList = sets.Data.OrderBy(s => s.Name).Select(s => new SelectListItem(s.Name, s.Code)).ToList();

            var selectedItem = SetList.FirstOrDefault(li => li.Value.Equals(set));

            if (selectedItem is not null)
            {
                selectedItem.Selected = true;
                CardList = (await _scryfallApi.Cards.Search($"e:{selectedItem.Value}", 1, SearchOptions.CardSort.Name)).Data;
            }
            else
            {
                CardList = new List <Card>();
            }

            return(Page());
        }