.net 2.0 cache problem

hi,

ill try and make this as brief as i can, i am having some problems with caching with VS.NET 2005 and .NET 2.0.

i have the following code which loads the content of an xml file into a hashtable and then caches the hashtable for later use.

private static void LoadResource(ResourceManagerType resourceType, Hashtable target, String language, String cacheKey)
{
String filePath = HttpContext.Current.Server.MapPath("~/Themes/Languages/" + language + "/{0}");
switch (resourceType)
{
case ResourceManagerType.String:
filePath = String.Format(filePath, "Resources.xml");
break;
case ResourceManagerType.Image:
filePath = String.Format(filePath, "Images.xml");
break;
}
CacheDependency dp = new CacheDependency(filePath);
XmlDocument d = new XmlDocument();
try
{
d.Load(filePath);
}
catch
{
return;
}
foreach (XmlNode n in d.SelectSingleNode("root").ChildNodes)
{
if (n.NodeType != XmlNodeType.Comment)
{
switch (resourceType)
{
case ResourceManagerType.String:
case ResourceManagerType.Image:
if (target[n.Attributes["name"].Value] == null)
{
target.Add(n.Attributes["name"].Value, n.InnerText);
}
else
{
target[n.Attributes["name"].Value] = n.InnerText;
}
break;
}
}
}
DateTime cacheUntil;
if (language == EnigmaConfiguration.GetConfig().DefaultLanguage)
{
cacheUntil = DateTime.MaxValue;
}
else
{
cacheUntil = DateTime.Now.AddHours(1);
}
HttpContext.Current.Cache.Insert(cacheKey, target, dp, cacheUntil, TimeSpan.Zero); // this sometimes fails to insert into the cache and the resultant check for cacheKey in the cache returns null
}

My question is simply this, is there a problem with cacheing in .net 2.0, it seems that on some occasions cache.Insert(...) fails to insert the data into the cache and result in a null reference exception. I never had this problem before in .net 1.1 or .net 1.0.

Any help would be appreciated

Regards
Neil

Hi Neil, you don't seem to be alone with this problem. Have you managed to
find out what it was? I'm experiencing a similar problem but with the
HttpRuntime.Cache (which supposedly is the same...although Rob Howard
suggests there's a perf. penalty when using it which suggests there's some
difference...).

A few posts regarding this has been posted today.

Thanks,
Manso

"Neil Stevens" wrote:

hi,

ill try and make this as brief as i can, i am having some problems with caching with VS.NET 2005 and .NET 2.0.

i have the following code which loads the content of an xml file into a hashtable and then caches the hashtable for later use.

private static void LoadResource(ResourceManagerType resourceType, Hashtable target, String language, String cacheKey)
{
String filePath = HttpContext.Current.Server.MapPath("~/Themes/Languages/" + language + "/{0}");
switch (resourceType)
{
case ResourceManagerType.String:
filePath = String.Format(filePath, "Resources.xml");
break;
case ResourceManagerType.Image:
filePath = String.Format(filePath, "Images.xml");
break;
}
CacheDependency dp = new CacheDependency(filePath);
XmlDocument d = new XmlDocument();
try
{
d.Load(filePath);
}
catch
{
return;
}
foreach (XmlNode n in d.SelectSingleNode("root").ChildNodes)
{
if (n.NodeType != XmlNodeType.Comment)
{
switch (resourceType)
{
case ResourceManagerType.String:
case ResourceManagerType.Image:
if (target[n.Attributes["name"].Value] == null)
{
target.Add(n.Attributes["name"].Value, n.InnerText);
}
else
{
target[n.Attributes["name"].Value] = n.InnerText;
}
break;
}
}
}
DateTime cacheUntil;
if (language == EnigmaConfiguration.GetConfig().DefaultLanguage)
{
cacheUntil = DateTime.MaxValue;
}
else
{
cacheUntil = DateTime.Now.AddHours(1);
}
HttpContext.Current.Cache.Insert(cacheKey, target, dp, cacheUntil, TimeSpan.Zero); // this sometimes fails to insert into the cache and the resultant check for cacheKey in the cache returns null
}

My question is simply this, is there a problem with cacheing in .net 2.0, it seems that on some occasions cache.Insert(...) fails to insert the data into the cache and result in a null reference exception. I never had this problem before in .net 1.1 or .net 1.0.

Any help would be appreciated

Regards
Neil