public async Task OnGetAsync(string tag = "") { long?parentId = null; if (!string.IsNullOrEmpty(tag)) { var column = await _columnService.GetOneAsync(new ColumnSearch { IsDeleted = false, Tag = tag }); parentId = column?.Id; } Columns = await _columnService.GetListAsync(new ColumnSearch { IsDeleted = false, ParentId = parentId }, "OrderIndex asc"); }