更高效的Linq表达

Question

I have this Linq Join

var NewQuote = (from qw in Q
                        join NW in NewNotes on qw.RECID equals NW.RECID into temp
                        from j in temp
                        select new Quotes
                        {
                            QuoteNumber = qw.QuoteNumber,
                            CustPartNumber = qw.CustPartNumber,
                            ITEMGROUPID = qw.ITEMGROUPID,
                          LotSize = qw.LotSize,
                          EAU = qw.EAU,
                          CONTACTPERSONID = qw.CONTACTPERSONID,
                          QUOTATIONSTATUS = qw.QUOTATIONSTATUS,
                          QUOTESENTDATE = qw.QUOTESENTDATE,
                          PricePerPiece = qw.PricePerPiece,
                          QuoteValue = qw.QuoteValue,
                          Email = qw.Email,
                          RECID = qw.RECID,
                          Notes = j == null ? "" : j.NOTES
                        }).ToList();

Q is of the Quote class but I need to add the data to the Notes field from NewNotes. Is there a better way to do this than listing every field from the Quote class? If I have to add fields to Quote then I have to document to come to this section of code and update as well.

Answer 1

Why you create new instances of Quotes if you just want to update one property?

var query = from qw in Q join NW in NewNotes 
            on qw.RECID equals NW.RECID into temp 
            from j in temp
            select new { Quote = qw, Notes = j?.Notes ?? "" };

foreach(var x in query)
{
    x.Quote.Notes = x.Notes;
}