在Linq表达式中创建XElement项

问题是它试图用SQL来实现吗?如果是这样,您只需要将SQL中要执行的位和linqto对象中要执行的位分开。试试这个:

var query = from t in ctx.Transactions
            where t.MessageRecievedAt >= Start && t.MessageRecievedAt <= End
            select new
            {
                t.DeviceId,
                t.Message,
                TransactionTime = t.EventTime_Local
            };
var transactionList = query.AsEnumerable() // LINQ to Objects from here
                           .Select(t => new TerminalTransactionMessage 
                                   {
                                      DeviceId = t.DeviceId,
                                      RawXMLDocument = XElement.Parse(t.Message),
                                      TransactionTime = t.TransactionTime
                                   });
                           .ToList();