我收到以下錯誤:當我嘗試返回查詢實體列表時,「無法翻譯表達式...」,轉換爲自定義類。無法翻譯表達式
我很新,以這種方式使用鏈接,在過去我會在SQL中使用存儲過程,只是將它們作爲方法導入,但我試圖轉換這些。
我返回列表的方法是:
public static List<EnquiryData> GetAllEnquiries()
{
var GridData = from a in Global.AcepakSalesPortal.Enquiries
join Cust in Global.AcepakSalesPortal.Customers
on a.CustomerID equals Cust.CustomerID into CustGroup
from b in CustGroup.DefaultIfEmpty()
join Pros in Global.AcepakSalesPortal.Prospects
on a.ProspectID equals Pros.ProspectID into ProsGroup
from c in ProsGroup.DefaultIfEmpty()
join Users in Global.AcepakSalesPortal.Users
on a.ResponsiblePartyID equals Users.UserID into UserGroup
from d in UserGroup.DefaultIfEmpty()
join Qt in Global.AcepakSalesPortal.Quotes
on a.QuoteID equals Qt.QuoteID into QuoteGroup
from e in QuoteGroup.DefaultIfEmpty()
join Usr in Global.AcepakSalesPortal.Users
on e.CreatedBy equals Usr.UserID into UsrGroup
from f in UsrGroup.DefaultIfEmpty()
join EnqCat in Global.AcepakSalesPortal.EnquiryCategories
on a.EnquiryCategoriesID equals EnqCat.EnquiryCatID into CatGroup
from g in CatGroup.DefaultIfEmpty()
join Clsd in Global.AcepakSalesPortal.Users
on a.ClosedBy equals Clsd.UserID into ClsdGroup
from h in ClsdGroup.DefaultIfEmpty()
orderby a.Created descending
select new EnquiryData
{
EnquiryID = a.EnquiryID,
ResponsiblePartyID = a.ResponsiblePartyID,
EnquiryNo = "ENQ" + a.EnquiryID.ToString().PadLeft(7, '0'),
EType = a.CustomerID.HasValue ? "C" : "P",
EnqCat = g.Code + " - " + g.Category,
ContactPerson = a.ProspectID.HasValue ? c.ContactPerson : "NOT INTEGRATED YET",
ContactNumber = a.ProspectID.HasValue ? c.ContactNum : "NOT INTEGRATED YET",
ContactEmail = a.ProspectID.HasValue ? c.ContactEmail : "NOT INTEGRATED YET",
Company = a.CustomerID.HasValue ? b.Name : c.CompanyName,
Description = a.Description,
AssignedTo = d.Name,
AddressBy = a.AddressBy,
EnquiryDate = a.Created,
EStatus = a.Closed.HasValue ? "Closed" : a.QuoteID.HasValue ? "Quoted" : "Open",
QuotedOn = a.QuoteID.HasValue ? e.Created.ToShortDateString() : "N/A",
QuotedBy = a.QuoteID.HasValue ? f.Name : "N/A",
QuoteNum = a.QuoteID.HasValue ? e.QuoteID.ToString().PadLeft(7, '0') : "N/A",
ClosedOn = a.Closed.HasValue ? a.Closed.Value.ToShortDateString() : "N/A",
ClosedBy = a.Closed.HasValue ? h.Name : "N/A",
Reason = a.Closed.HasValue ? a.ClosedReason : "N/A"
};
return GridData.ToList();
}
和自定義類是:
public class EnquiryData
{
public int EnquiryID { get; set; }
public int ResponsiblePartyID { get; set; }
public string EnquiryNo { get; set; }
public string EType { get; set; }
public string EnqCat { get; set; }
public string ContactPerson { get; set; }
public string ContactNumber { get; set; }
public string ContactEmail { get; set; }
public string Company { get; set; }
public string Description { get; set; }
public string AssignedTo { get; set; }
public DateTime AddressBy { get; set; }
public DateTime EnquiryDate { get; set; }
public string EStatus { get; set; }
public string QuotedOn { get; set; }
public string QuotedBy { get; set; }
public string QuoteNum { get; set; }
public string ClosedOn { get; set; }
public string ClosedBy { get; set; }
public string Reason { get; set; }
}
我的問題是2倍 1.是否有更好的方式來表連接在一起的Linq比我在上面做得更多? 2.什麼可能會導致錯誤,我不介意搞清楚,但不知道如何甚至接近這一點。
編輯:這絕對不是上述問題的重複。 2之間唯一的相似之處在於使用了shortdatestring,但是我收到的錯誤消息與另一個問題完全不同。
你能告訴什麼是當你剛做這樣的問題'選擇了',而不是自定義類mapper.tell我們嗎? – Sampath
使用select時,它將記錄通過正常,沒有任何例外。所以我猜測這是一些不滿意的轉換。 – ThatChris
context.Database.Log =(sw)=> Debug.WriteLine(sw);你可以在聲明你的查詢之前包含這一行。並在VS的輸出窗口中查找已翻譯的查詢和執行。上下文是你的DbContext名稱 – Raghu