Caching

[RFH Reseller: spire128]

Hi

Well I have Googled for hours to no avail so I am hoping there is an Asp.Net 2.0 guru on here that knows about caching.

Okay so on my forms in the code behind VB flavour I put some site settings into cache (I check first to see if the cache has been ejected) if it has I then run the following code:

'Create New Object SiteSettings
Dim myCacheSiteSettings As New SiteSettingsCs

'Load SiteSettings Data
myCacheSiteSettings.SiteName = GetSharedSettings.SiteName

' Insert the Cache into memory
Cache.Insert("SiteSettings", myCacheSiteSettings, Nothing, System.Web.Caching.Cache.NoAbsoluteExpiration, TimeSpan.FromMinutes(15))

Works great

Now the problem is that I am doing this on every page I need the site settings, what I would like to do is get the above routine into 1 place in a class for example where I can call it to reload the cache.

But so far I have been unable to workout how to do this

So can anyone point me in the right direction please

Thanks

[RFH Reseller: Sol]

Here's how I would do it in C#

public class SiteSettingsManager
{
    //we don't want to instantiate this class.
    private SiteSettingsManager()
    {}


    public static SiteSettingsCs GetSiteSettings()
    {
        SiteSettingsCs siteSettings = Cache["SiteSettings"];
        if (siteSettings == null)
        { 
             // the SiteSettings were not in the cache so create them
             siteSettings = new SiteSettings();

             // put result in the cache
             Cache.Insert("SiteSettings", siteSettings, null, Cache.NoAbsoluteExpiration, TimSpan.FromMinutes(15));
        }

        return siteSettings;
}

[RFH Reseller: spire128]

Hi

But this line of code won't complie

Insert the Cache into memory
Cache.Insert("SiteSettings", myCacheSiteSettings, Nothing, System.Web.Caching.Cache.NoAbsoluteExpiration, TimeSpan.FromMinutes(15))

Gives this error
reference to a non shared member requires an object reference

[RFH Reseller: Sol]

Try wrapping the Cache class:

public class MyCache
{
  private static readonly System.Web.Caching.Cache m_cache;
 
  ///<summary>
  /// Static initializer should ensure we only have to look up the current cache
  /// instance once.
  ///</summary>
  static MyCache()
  {
      HttpContext context = HttpContext.Current;
      if (context != null)
      {
           m_cache = context.Cache;
       }
       else
       {
           m_cache = HttpRuntime.Cache;
        }
   }
 
   ///<summary>
   /// Removes all items from the Cache
   ///</summary>
   public static void Clear()
   {
         IDictionaryEnumerator CacheEnum = m_cache.GetEnumerator();
         while (CacheEnum.MoveNext())
             m_cache.Remove(CacheEnum.Key.ToString());
    }
 
    ///<summary>
    /// Removes the specified key from the cache
    ///</summary>
    ///<param name="key"></param>
    public static void Remove(string key)
    {
          m_cache.Remove(key);
     }
 
     ///<summary>
     /// Insert the current "obj" into the cache. 
     ///</summary>
     ///<param name="key"></param>
    ///<param name="obj"></param>
    public static void Insert(string key, object obj)
    {
          Insert(key, obj, null, 1);
     }
 
     public static void Insert(string key, object obj, int seconds, CacheItemPriority priority)
     {
           Insert(key, obj, null, seconds, priority);
      }
 
      public static void Insert(string key, object obj, CacheDependency dep, int seconds, CacheItemPriority priority)
     {
            if (obj != null)
           {
                  m_cache.Insert(key, obj, dep, DateTime.Now.AddSeconds(m_factor * seconds), TimeSpan.Zero, priority, null);
           }
      }
 
      public static object Get(string key)
      {
            return m_cache[key];
      }
 
}

I should also point out that doing this allows you to use the cache from Windows Forms applications.