Linq用Lambda计数左联接

Question

我有一个Users和一个Shipments表。 Shipments表具有属性Received。我想编写代码以使用linq获取所有已收到其所有货件（Users）的所有received == true。

[Users表

public Guid Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public bool NeedsFilament { get; set; }
public ICollection<Shipment> Shipments { get; set; }

Shipments表

public Guid Id { get; set; }
public int Quantity { get; set; }
public DateTime DateShipped { get; set; }
public bool Recieved { get; set; }
public Guid UserId { get; set; } 
public User User { get; set; }

[到目前为止，我在SQL查询中所做的不算Received中的Shipments道具，而只是获得了区别（这是错误的）

SELECT DISTINCT
    [FirstName]
    ,[LastName]
    ,[Username]
    ,[Address]
    ,[LatestShippedDate]
    ,[PrinterActive]
    ,[ProductionDate]
    ,[ShippedQuantity]
    ,[Email]
    ,[PhoneNumber]
    ,[NeedsFilament]
    ,[FilamentTrackingNumber]
    ,[SentFilamentDate]
    ,[LatestShippedQuantity]
FROM 
    [dbo].[Users]
LEFT JOIN 
    Shipments ON Shipments.UserId = Users.Id
WHERE 
    Shipments.Recieved = 1 
    AND Users.NeedsFilament = 1

Answer 1

Hello @ Pt4r，下面的Linq语句将完成您想要的操作，下面的行解析users_table并比较两个表的每个元素，并保留那些语句返回true的元素

var newUserTbl = users_table.Where(user=>Shipments.UserId==user.id && Shipments.Recieved).ToList();