C# Linq到实体查询，子查询返回错误

我有一个Linq到实体的查询，其中有一个子查询返回一个错误，我希望有人能帮我解决

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))
};

提前感谢,

克里斯

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)
    };

---

为什么不使用关系？哪些对象或属性的类型为

TransactionAllocation

？这只是

smallBusinessManagerDB.TransactionAllocation

？感谢您的回复。我做了改变，但是，同样的错误发生了。无法创建“SmallBusinessManager.Models.TransactionAllocation”类型的常量值。在此上下文中仅支持基本类型（“如Int32、字符串和Guid”）。如果只执行

var x=smallBusinessManagerDB.Transaction.ToList（）

和

var y=smallBusinessManagerDB.TransactionAllocation.ToList（），会发生什么情况

？x以System.Collection.Generic.List的形式返回数据库中的所有记录，y以System.Collection.Generic.List的形式返回数据库中的所有记录database@ChrisNieu-你能接受我的查询，评论余额设置器并检查它是否有效吗？（试图将此问题本地化）