Linq到子查询的实体查询返回错误

Question

我有一个Linq到实体查询与一个子查询返回一个错误，我希望有人能够帮助我。

错误消息：

"Unable to create a constant value of type 'SmallBusinessManager.Models.TransactionAllocation'. Only primitive types ('such as Int32, String, and Guid') are supported in this context." 

LINQ查询：

var query = from transactionSelect in smallBusinessManagerDB.Transaction 
     select new 
     { 
     TransactionId = transactionSelect.TransactionId, 
     TransactionNumber = transactionSelect.TransactionNumber, 
     Amount = transactionSelect.Amount, 
     Balance = (from t2 in smallBusinessManagerDB.TransactionAllocation 
        where t2.InvoiceTransactionId == transactionSelect.TransactionId 
        group t2 by t2.TransactionAllocationId into g 
        select g.Sum(p => p.AllocatedAmount)) 
}; 

由于提前，

克里斯

Answer 1

试试这个：

var query = 
    from transactionSelect in smallBusinessManagerDB.Transaction 
    select new 
    { 
     TransactionId = transactionSelect.TransactionId, 
     TransactionNumber = transactionSelect.TransactionNumber, 
     Amount = transactionSelect.Amount, 
     Balance = smallBusinessManagerDB.TransactionAllocation 
      .Where(t2 => t2.InvoiceTransactionId == transactionSelect.TransactionId) 
      .Sum(p => p.AllocatedAmount) 
    };