试图从数据库中获取列表并将其保存在我的程序内部。(Trying to get at list from database and save it internally in my program. Getting ObjectContext errors)

 我创建了一个应用程序（这是一个学校项目）。 那是连接到数据库。 由于实体框架，所有这一切都很有效。 
 
 我遇到的问题如下。 
 
 我的c＃代码中有一类客户。 这些Customers拥有public virtual list<Accounts> 。 
 
 在数据库中，我有以下表，客户和帐户。 Account类具有属性public virtual Customer Customers {get; set;} public virtual Customer Customers {get; set;} 
 
 我有一个单独的类，它有一个我想要从数据库更新的list<Customer> 。 
 
using (var db = new dbcontext())
{
    list<Customer> templist = new list<Customer>
    var query = from dbCust in db.Customers
            select dbcust;

    foreach (Customer cust in query)
    {
       (templist.add(cust)
    }

   return new list<Customer>(templist);
 
 所以我呼吁像customers = dbmethod(); 它应该返回新列表和templist的副本。 
 
 但是当我尝试使用该列表时，当我尝试访问客户中的帐户时，我收到以下错误： 
 
 
 
 ObjectContext实例已被释放，不能再用于需要连接的操作。“ 
 

I have created an app (this is for a school project). That is to be connected to a database. All this works great thanks to Entity Framework. 
 
The problem I'm encountering is the following.
 
I have a class of customers in my c# code. These Customers have public virtual list<Accounts>. 
 
In the database I have the following tables, Customers and Accounts. The Account class has a property public virtual Customer Customers {get; set;}
 
I have a separate class that has a list<Customer> that I want to update from the database.
 
using (var db = new dbcontext())
{
    list<Customer> templist = new list<Customer>
    var query = from dbCust in db.Customers
            select dbcust;

    foreach (Customer cust in query)
    {
       (templist.add(cust)
    }

   return new list<Customer>(templist);
 
So i call for like customers = dbmethod(); it should return the new list and the copies of templist. 
 
But when i try to use the list i get the following error when i try to access the accounts in a customer:
 
 
 
The ObjectContext instance has been disposed and can no longer be used for operations that require a connection." 
 

原文：https://stackoverflow.com/questions/34296992