如何彙總Linq查詢中的字符串列表？

我需要最終使我的MVC表中的列有一串OrderNumbers。我似乎無法找出已經擁有的如何彙總Linq查詢中的字符串列表？

public IEnumerable<OrderShippedListModel> GetRecentShippedOrders(string authenticatedUsername) 
{ 
    User currentUser = new User().GetUser(authenticatedUsername); 
    Order (from r in dc.Orders 
      where r.Location.OrganizationID == currentUser.OrganizationID 
      && r.CloseDate != null 
      && r.ProductShipDate != null 
      orderby r.LastModifiedDate descending 
      select new OrderShippedListModel 
      { 
       ID = r.ID, 
       OrderNumbers = r.Processes.Select(p=>p.OrderNumber), //This needs to aggregate to a string 
       Label = r.Label, 
       Location = r.Location.Label, 
       CreateDate = r.CreateDate, 
       ProductShipDate = r.ProductShipDate, 
       LastModifiedDate = r.LastModifiedDate, 
       CloseDate = r.CloseDate 
      }).Take(3); 
}

集合這裏是我的類模型

public class OrderShippedListModel 
{ 
    public int ID { get; set; } 

    public string Label { get; set; } 

    public string Location { get; set; } 

    [Display(Name = "Create Date")] 
    public DateTime CreateDate { get; set; } 

    [Display(Name = "Last Modified Date")] 
    public DateTime LastModifiedDate { get; set; } 

    [Display(Name = "Product Ship Date")] 
    public DateTime? ProductShipDate { get; set; } 

    [Display(Name = "Close Date")] 
    public DateTime? CloseDate { get; set; } 

    [Display(Name = "Job Numbers")] 
    public string OrderNumbers { get; set; } 
}

來源

2014-02-22 EdenMachine

使用string.Join：

OrderNumbers = string.Join("", r.Processes.Select(p=>p.OrderNumber)),

來源

2014-02-22 15:14:17 Alberto

另一個是彙總：

var s = r.Processes.Aggregate((accum, elem) => accum += elem.OrderNumber)

來源

2014-02-22 15:18:12 Paul

這效率顯着降低因爲它會導致創建大量的中間字符串，因此會花費大量的時間分配新的字符緩衝區，並在緩衝區之間一遍又一遍地複製相同的數據。 – Servy

我不知道這是效率低下，謝謝你指出這一點。 – Paul

如何彙總Linq查詢中的字符串列表？

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