在我们的项目中,我们使用MefControllerFactory,这些是我们在global.asax中设置为application_start的代码ControllerBuilder.Current.SetControllerFactory(new Project.Helper.MefControllerFactory(container));
问题是当我们在结果中运行.NET Profiler时,即使我们在“ReleaseController”方法中配置控制器也会出现内存泄漏问题。原始消息是“实例已处理但仍可从一个或多个根处访问。由于通常不再使用已处置的实例,这可能表示内存泄漏。调查实例以查明实例是否是无意的保持活力,或者如果问题可以忽略。“ 有没有解决这个问题的方法?
第二条消息是: “具有直接EventHandler根的已处置实例 已处置的实例直接由EventHandler生成,即该实例仅用作EventHandler的目标,并且不通过委托就无法从任何其他根目录访问它。由于不再使用已处置的实例,并且EventHandler是内存泄漏的常见原因,因此该问题是内存泄漏的强烈迹象。“
public class MefControllerFactory : IControllerFactory
{
private CompositionContainer _container;
private DefaultControllerFactory defaultControllerFactory;
public MefControllerFactory(CompositionContainer container)
{
_container = container;
this.defaultControllerFactory = new DefaultControllerFactory();
}
#region IControllerFactory Members
public IController CreateController(System.Web.Routing.RequestContext requestContext, string controllerName)
{
IController controller = null;
controller = _container.GetExportedValueOrDefault<IController>(controllerName);
if (controller == null)
return this.defaultControllerFactory.CreateController(requestContext, controllerName);
return controller;
}
public void ReleaseController(IController controller)
{
IDisposable disposable = controller as IDisposable;
if (disposable != null)
disposable.Dispose();
}
#endregion
public System.Web.SessionState.SessionStateBehavior GetControllerSessionBehavior(System.Web.Routing.RequestContext requestContext, string controllerName)
{
return System.Web.SessionState.SessionStateBehavior.Default;
}
}
...谢谢
答案 0 :(得分:5)
这是我为my book的代码示例创建的基于MEF的控制器工厂:
public class MefControllerFactory : DefaultControllerFactory
{
private readonly CompositionContainer container;
private readonly Dictionary<IController, Lazy<object, object>> exports;
private readonly object syncRoot;
public MefControllerFactory(CompositionContainer container)
{
if (container == null)
{
throw new ArgumentNullException("container");
}
this.container = container;
this.exports = new Dictionary<IController, Lazy<object, object>>();
this.syncRoot = new object();
}
protected override IController GetControllerInstance(
RequestContext requestContext, Type controllerType)
{
var export = this.container.GetExports(
controllerType, null, null).Single();
var controller = (IController)export.Value;
lock (this.syncRoot)
{
this.exports.Add(controller, export);
}
return controller;
}
public override void ReleaseController(IController controller)
{
lock (this.syncRoot)
{
var export = this.exports[controller];
this.exports.Remove(controller);
this.container.ReleaseExport(export);
}
base.ReleaseController(controller);
}
}
在MEF中,您只能通过发布导出而不是导出的值来释放对象图。