The ObjectContext instance has been disposed and can no longer be used for operations that require a connection. How to solve the error The ObjectContext instance has been disposed and can no longer be used for operations that require a connection 1.…
The ObjectContext instance has been disposed and can no longer be used for operations that require a connection. public static List<Menu> Get(int appid) { List<Menu> menuList = null; using(wechatEntities ctx=new wechatEntities()) { //disable l…
The ObjectContext instance has been disposed and can no longer be used for operations that require a connection 该对象上下文实例已被释放,不能用于需要连接的操作. shared context per request模式,缩短Entity实例的存在时间和降低Entity实例的共享性,并考虑性能,因为Entity需要手动Dispose. public override void Disp…
Performance Considerations for Entity Framework 5 By David Obando, Eric Dettinger and others Published: April 2012 1. Introduction Object-Relational Mapping frameworks are a convenient way to provide an abstraction for data access in an object-orient…
C# using 用法: 1. 作为指令,用于为命名空间创建别名或导入其他命名空间中定义的类型.(见例1-1) 2. 作为语句,用于定义一个范围,在此范围的末尾将释放对象.(见例1-2) (例子1-1) ① 允许在命名空间中使用类型,这样,您就不必在该命名空间中限定某个类型的使用 using System.ServiceModel; ② 为命名空间或类型创建别名 ③ 等同于Try.{}Finally{}在语句结束时自动执行. public class Foo: IDisposable 2 {…