Question

这是我用来获取具有特定ID的商品和每个商品的商品详细信息的查询

public class ItemModel 
{
   public int ItemSeq{get;set}
   public string ItemName{get;set;}
   public double? Amount{get;set;}
}
public class SampleModel
{
    public string Id{ get; set; }
    public string Code{ get; set; }
    public List<ItemModel> Items{ get; set; }
}

public List<SampleModel> GetItems(string id)
{

    var items= _context.ItemTable.Where(t => t.Id== id).ToList<SampleModel>();
    return list;
}

为明确要求，有两个表ItemTable和ItemDetailTable，而Id是ItemTable中的ItamDetailTable主键和外键，而{{ 1}}对于单个ItemDetailTable可能具有多个值，并且上面的查询从ID返回项目和具有特定ID的详细信息，我想要的是具有按值排序的项目详细信息值ItemDetailTable。有什么办法吗？

样本数据

ItemTable

Amount

ItemDetailTable

Id     Code
1      Code1
2      Code3

我想要的是Id ItemSeq ItemName Amount 1 1 ABC1 200 1 2 ABC2 129 1 3 ABC3 549 2 1 DEF1 265 2 2 DEf2 970的值为1时返回的值

Id

Answer 1

您需要通过将ItemModel参数传递给id方法来返回GetItems的排序列表。

public List<ItemModel> GetItems(string id)
{
    var items = _context.SampleTable.Where(t => t.Id == id).SelectMany(x => x.Items).Where(p => p.Amount != null).OrderBy(x => x.Amount).ToList();
    return items.ToList();
}

编辑：

上面的查询从ItemDetailTable返回具有特定ID的项目和详细信息

您还需要将外键属性添加到ItemDetailTable中，如

public class ItemDetailTable
{
    public int ItemSeq { get; set; }
    public string ItemName { get; set; }
    public double? Amount { get; set; }

    public string Id { get; set; }   //Foreign key of ItemTable
}


public ItemTable GetItems(string id)
{
    //Get "ItemTable" record from database
    var item = _context.ItemTable.Where(x => x.Id == id).SingleOrDefault();

    //Retrieve its "Items" and sort by ascending order
    var itemDetails = item.Items.Where(x => x.Id == id).Where(p => p.Amount != null).OrderBy(x => x.Amount).ToList();

    //Preare a new "ItemTable" object to return
    ItemTable itemTable = new ItemTable
    {
        Code = item.Code,
        Id = item.Id,
        Items = itemDetails
    };

    //Return new "itemTable" with sorted list of "ItemDetailTable"
    return itemTable;
}

编辑2：

public ItemTable GetItems(string id)
{
    var result = (from i in _context.ItemTable
                  where i.Id == id
                  let sorting = i.Items.Where(x => x.Id == id).Where(x => x.Amount != null).OrderBy(x => x.Amount).ToList()
                  select new ItemTable
                  {
                      Id = i.Id,
                      Code = i.Code,
                      Items = sorting
                  }).FirstOrDefault();   //Or => SingleOrDefault

    return result;
}

如何对对象中的对象值列表进行排序

1 个答案: