如何我可以通過我的全部郵件組

Question

我試圖讓每個用戶的所有郵件的數量

msg 1 = SenderId =1 , ReciverId =2 
msg 2 = SenderId =2 , ReciverId =1 
msg 3 = SenderId =1 , ReciverId =2 

我在我的例子 考慮1個使用相同的用戶作爲一個消息聊天等等查詢需要reurn，我有一個消息

這是什麼查詢？ 我寫了一個查詢底部，告訴我想要什麼 但是迴腸，我怎麼寫一個工作？

public class UserMessages 
{ 
    public long Id { get; set; } 
    public long SenderId { get; set; } 
    public long ReciverId { get; set; } 
    public string Text { get; set; } 
    public DateTime? DateTime { get; set; } 
    public bool FastMessage { get; set; } 
    public bool SenderDelete { get; set; } 
    public bool ReciverDelete { get; set; } 
    public bool ReciverRead { get; set; } 
} 

     var UserMessages = db.UserMessages 
          .Where(x => (x.SenderId == id && x.SenderDelete == false) || 
             (x.ReciverId == x.Id && x.ReciverDelete == false)) 
          .GroupBy(x => new { x.ReciverId, x.SenderId }) 
          .GroupBy((y, w) => y.Key.SenderId == w.Key.ReciverId 
               && y.Key.ReciverId == w.Key.SenderId) 
          .Count(); 

Answer 1

我採取的是這樣的：

var result = db.UserMessages 
       .Where(x => x.SenderId == id || x.ReceiverId == id) 
       .Select(x => x.ReceiverId == id ? x.SenderId : x.ReceiverId) 
       .Distinct() 
       .Count(); 

Answer 2

var id = 1; // the ID of the person to count chat partners for 

var chatPartnerCount = db.UserMessages 
    .Where(x => x.SenderId == id && !x.SenderDelete || x.ReceiverId == id && !x.ReceiverDelete) 
    .GroupBy(x => x.SenderId == id ? x.ReceiverId : x.SenderId) // group by the chat partner 
    .Count(); // count the number of unique chat partners