Reference Cache or Application from a class

pauliehaha · April 17th, 2007, 08:06 AM

Hi,

I store some key/value strings used by my application in a table, there are about 30-40 items.

I have a class which loads the values from the database and stores them in a string dictionary as key/value pairs.

I want to persist this collection throughout the lifetime of the application and perform a lookup on the collection whenever and wherever I need to.

So I invoke the load method of the class in the Application_Start method in global.asax.

In my load method I want to assign the dictionary to the Cache or application object.

The problem I am having is with referencing either the Cache or Application object from this class.

Here's an example of where I am, which causes a "Object reference not set to an instance of an object." error:

Code:

Imports System
Imports System.Web
Imports System.Web.Caching
Imports System.Collections
Imports System.Collections.Specialized

Public Class AppString

Public Shared myCache As New Cache

Public Shared Sub LoadStrings()

 ' Creates and initializes a new StringDictionary.
 Dim myStrings As New StringDictionary()

 myStrings.Add("STRING1", "Value 1")
 myStrings.Add("STRING2", "Value 2")
 myStrings.Add("STRING3", "Value 3")

 myCache("LanguageStrings") = myLanguageStrings

Which one would be best, Cache or Application, for this amount of items and how do I get a reference to it so I can assign my dictionary to it?

Many Thanks,

Paulie

http://www.thewebsiteshop.co.uk

pauliehaha · April 17th, 2007, 09:51 AM

It's really easy - I got confused with all the different resources on the web discussing this

My changed code below works:

Code:

Imports System
Imports System.Web.HttpContext
Imports System.Collections
Imports System.Collections.Specialized

Public Class AppString

Public Shared Sub LoadStrings()

 ' Creates and initializes a new StringDictionary.
 Dim myStrings As New StringDictionary()

 myStrings.Add("STRING1", "Value 1")
 myStrings.Add("STRING2", "Value 2")
 myStrings.Add("STRING3", "Value 3")

 Current.Cache("myStrings") = myStrings

Thanks,

Paulie

http://www.thewebsiteshop.co.uk