将ViewState转存到文件

基本上是从网上抄的，何时清理过时的ViewState，我的想法是Session_End。

为所有页面定义基类，重载下面两个方法：

public class PageBase : Page{ private string AppDataPath { get { return Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "App_data"); } } protected override void SavePageStateToPersistenceMedium(object state) { string encodedUrl = BitConverter.ToString(MD5.Create().ComputeHash(Encoding.Default.GetBytes(Request.Path.ToLowerInvariant()))).Replace("-", ""); string viewStateID = Session.SessionID + encodedUrl + DateTime.Now.Ticks.ToString(); string value = new ObjectStateFormatter().Serialize(state); string fileName = Path.Combine(AppDataPath, viewStateID); ThreadPool.QueueUserWorkItem(obj => File.WriteAllText(fileName, value)); Cache.Insert(viewStateID, value); base.SavePageStateToPersistenceMedium(viewStateID); } protected override object LoadPageStateFromPersistenceMedium() { string viewStateID = (string)((Pair)base.LoadPageStateFromPersistenceMedium()).Second; string value; if (Cache[viewStateID] == null) { string fileName = Path.Combine(AppDataPath, viewStateID); value = File.ReadAllText(fileName); } else { value = (string)Cache[viewStateID]; } return new ObjectStateFormatter().Deserialize(value); }} 

在Global.asax.cs中：

protected void Session_End(Object sender, EventArgs e){ string viewStatePath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "App_Data"); DirectoryInfo directory = new DirectoryInfo(viewStatePath); foreach (FileInfo file in directory.GetFiles(Session.SessionID + "*", SearchOption.TopDirectoryOnly)) { file.Delete(); }} 

当然也可以人PageStatePesister或 PageAdapter入手。