我有一个ASP.NET 4 Web服务。
它在ModuleController
控制器中有一个ImportModule
动作。ASP.NET HttpContext缓存在插入后立即删除
这就是它是如何工作的:
- 用户上传模块作为CSV文件。
- 此文件正在使用
HttpPostedFileBase.InputStream
和自定义CSV阅读课程阅读。 - 根据一些规则和验证,将此文件转换为C#对象。如果文件有效,那么它将转换为C#对象,将其存储在具有唯一GUID名称的缓存中,并将用户重定向到
CompleteImportModule
操作。 - 用户检查数据是否正确,并确认上传。
长话短说,有它告诉你更多的是代码:
ImportModule
行动。
public ActionResult ImportModule(HttpPostedFileBase file)
{
if (!ModelState.IsValid)
{
return RedirectToAction("Index");
}
ModuleQuestion[] questions;
ModuleInfo moduleInfo;
string uploadId = Guid.NewGuid().ToString();
// It is my custom CSV-reader and it works. Values are assigned
FormDataCsvReader csvReader = new FormDataCsvReader(file.InputStream);
if (!csvReader.Process(out questions, out moduleInfo))
{
// File is invalid
return RedirectToAction("Index");
}
ViewBag.UploadId = uploadId;
ViewBag.ModuleInfo = moduleInfo;
ViewBag.Questions = questions;
HttpContext.Cache.Add("UploadModule_" + uploadId,
new Tuple<ModuleInfo, ModuleQuestion[]>(moduleInfo, questions),
null,
Cache.NoAbsoluteExpiration,
TimeSpan.FromMinutes(30),
CacheItemPriority.NotRemovable,
(k, v, r) =>
{
LoggingFactory.GetLogger().Debug("Removed from cache: {0}. Reason: {1}", k, r);
});
return View();
}
在View ImportModule
:
// Output data from ViewBag.ModuleInfo and ViewBag.Questions
<form method="POST" action="@Url.Action("CompleteImportModule")">
<input type="hidden" name="uploadId" value="@ViewBag.UploadId"/>
<input type="submit" value="Send">
</form>
CompleteImportModule
行动:
[HttpPost]
public ActionResult CompleteImportModule(string uploadId)
{
var item = HttpContext.Cache["UploadModule_" + uploadId];
if (item == null) RedirectToAction("Index");
// upload module
HttpContext.Cache.Remove("UploadModule_" + uploadId);
return RedirectToAction("Index");
}
不过,我遇到了一些问题。我无法上传模块,因为插入后该值将从缓存中删除。它存储只对第二:
DEBUG 2015-06-22 15:00:18,696 thread 85: Added to cache:
UploadModule_c843077d-21d0-4e9f-9e5e-3df82da4bac8
DEBUG 2015-06-22 15:00:19,935 thread 48: Removed from cache:
UploadModule_c843077d-21d0-4e9f-9e5e-3df82da4bac8. Reason: Removed
的reason
被“删除”,这意味着它没有过期,IIS没有它删除,由于优化,但它看起来像我去掉就是我自己。 我很肯定,我甚至没有访问此缓存记录之前CompleteImportModule
。
我试图把new StackTrace().ToString()
在CacheItemRemovedCallback
。就是这样,如果它能够以某种方式帮助:
at CPMAdministrator.Controllers.ModulesReferenceController.<ImportModule>b__9(String key, Object value, CacheItemRemovedReason reason)
at System.Web.Caching.CacheEntry.CallCacheItemRemovedCallback(CacheItemRemovedCallback callback, CacheItemRemovedReason reason)
at System.Web.Caching.CacheEntry.Close(CacheItemRemovedReason reason)
at System.Web.Caching.CacheSingle.UpdateCache(CacheKey cacheKey, CacheEntry newEntry, Boolean replace, CacheItemRemovedReason removedReason, Object& valueOld)
at System.Web.Caching.CacheSingle.Dispose(Boolean disposing)
at System.Web.Caching.CacheMultiple.Dispose(Boolean disposing)
at System.Web.HttpRuntime.Dispose()
at System.Web.HttpRuntime.ReleaseResourcesAndUnloadAppDomain(Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
at System.Threading.ThreadPoolWorkQueue.Dispatch()
为什么会发生这种情况?是否有点类似IIS池回收?我如何确保文件不被删除?或者我怎样才能以另一种方式有效地存储这些数据?
这是在生产环境还是通过VS进行调试? – heymega
@heymega这是VS开发人员的机器上调试。 –