如何将 LINQ 查询数据转换为 WPF/MVVM 列表

Question

我有两个实体：

 public class Transport
    {
        [Key]
        public int TransportID {get; set;}
        public string Model { get; set; }
        public string Brand { get; set; }
    }
    public class TransportOwner
    {
        [Key]
        public int TransportOwnerID {get; set;}
        public int OwnerID {get; set;}
        public int TransportID {get; set;}
        [ForeignKey("TransportID")]
        public virtual Transport Transport { get; set; }
    }

在 ViewModel 中，我从这两个实体创建了两个列表：

public List<Transport> TransportList 
public List<OwnerTransport> OwnerTransportList

我需要用这两个列表中的数据为我的 WPF/MVVM 表单构建第三个列表：我需要的结构是：

OwnerTransportID
OwnerID
TransportID
Model
Brand

我的 ViewModel.cs 下一步要做什么？我需要创建新的 class 吗？

public class OwnerTransportTransport
{
    [Key]
    public int OwnerTransportID {get; set;}
    public int TransportID {get; set;}
    public string OwnerID {get; set;}
    public string Model { get; set; }

    public string Brand { get; set; }
}

然后是

List<OwnerTransport> OwnerTransportTransportList

??你能帮忙吗？

我从 linq 查询得到的数据：

var ownerTransportList = OwnerTransport.Select(t => new
{
    t.OwnerTransportID,
    t.OwnerID,
    t.TransportID,
    ModelName = t.Transport.ModelName,
    BrandName = t.Transport.BrandName,
}).ToList();

所以我有数据，但不知道如何将其转换为 List<OwnerTransportTranspot>。

Answer 1

我创建了 class:

public class OwnerTransportTransport
{
  public int OwnerTransportID { get; set; }
  public int TransportID { get; set; }
  public string Brand { get; set; }
  public string Model { get; set; }
}

然后完成我需要的:)

var query = dbContext.TransportOwner.AsQueryable();
ListIWantToShow = new List<OwnerTransportTransport>();
foreach (var transport in query)
  {
    OwnerTransportTransport NewList = new OwnerTransportTransport
      {
        ID = transport.ID,
        TransportID = transport.TransportID,
        BrandName = transport.Transport.BrandName,
        ModelName = transport.Transport.ModelName
      };

        ListIWantToShow.Add(tranport);
   }

Answer 2

其实你可以这样做：

List<OwnerTransportTransport> ListIWantToShow =
                        (from transport in dbContext.TransportOwner
                        select new OwnerTransportTransport()
                        {
                            ID = transport.ID,
                            TransportID = transport.TransportID,
                            BrandName = transport.Transport.BrandName,
                            ModelName = transport.Transport.ModelName
                        }).ToList();


public class OwnerTransportTransport
{
  public int OwnerTransportID { get; set; }
  public int TransportID { get; set; }
  public string Brand { get; set; }
  public string Model { get; set; }
}

Answer 3

根据user3185569的回答，我是这样写的：

var query = DBContext.TransportOwner.AsQueryable()
.Where(st => st.OwnerID.StartsWith(someParam));

List<OwnerTransportTransport> ListIWantToShow = query.Select(transport => new OwnerTransportTransport()
                        {
                            ID = transport.ID,
                            TransportID = transport.TransportID,
                            BrandName = transport.Transport.BrandName,
                            ModelName = transport.Transport.ModelName

                        }).ToList();

至少我没有错误，但是将这段代码与foreach进行比较，花了这么长时间:(但是这个答案正是我所需要的！我会接受它

如何将 LINQ 查询数据转换为 WPF/MVVM 列表

How to convert LINQ query data to WPF/MVVM List

c#

linq

mvvm

entity-framework-6

devexpress-wpf