Problem with SiteProvider

Jack Gillespie · February 16th, 2010, 02:01 PM

I'm trying to implement ONLY the store portion of the Beer House WITHOUT any personalization, etc., Nor am I using memership since this will run on an internal intranet.

The problem I'm having is in the SiteProvider Class which only has the Store() property defined.

I receive the following for Return StoreProvider.Instance:

{value cannot be null:parameter name:Type}

The values of the storeElement from the web.config are created by not available here.

Can anyone provide suggestions on how to set the StoreProvider.Instance in this situation?

Lee Dumond · February 16th, 2010, 03:25 PM

It appears you are passing null to Activator.CreateInstance. The CreateInstance method requires the type of Globals.Settings.Store.ProviderType in order to create the instance.

It gets that type from the web.config, via the Settings property of the Globals class, which is being abstracted by the classes in the ConfigSection.cs file.

So, the question is - have you pulled in all of that functionality?

You will need to do that for this to work. Otherwise, if you don't require the ability to swap put providers, you could just hard-code the provider into the CreateInstance method.

Jack Gillespie · February 16th, 2010, 03:35 PM

Lee:

thanks for the quick response.

I have implemented all of the properties in the ConfigSection.vb and the Web.Config.

When stepping through the contents of the Globals.settings I can see all of the properties. It only becomes null when I hit the SiteProvider class. Here is the complete code of the SiteProvider class:

Imports Microsoft.VisualBasic
Namespace JG.BMTStore.DAL
Public NotInheritable Class SiteProvider
Public Shared ReadOnly Property Store() As StoreProvider
Get
Return StoreProvider.Instance
End Get

End Property
End Class
End Namespace

I've changed the namespace throughout the application.

Lee Dumond · February 16th, 2010, 04:02 PM

What I'm saying here is that the value that is returned as StoreProvider.Instance is derived from the Instance property in StoreProvider.cs (or, in your case, StoreProvider.vb). That is where you need to look.

The get clause of that Instance property is where the actual object is created by the Activator.CreateInstance method. You will see that the CreateIntance method requires a Type. If that Type is null, you will get an ArgumentNullException that says "value cannot be null. Parameter name:Type".

That means that Type.GetType(Globals.Settings.Store.ProviderType) that you are passing in here is probably null. You need to set a breakpoint here and debug to confirm that.

The only thing that could make this clause return null is that your application cannot find a defined type of Globals.Settings.Store.ProviderType. That would indicate a problem with your configuration settings or classes.

Jack Gillespie · February 16th, 2010, 04:30 PM

Lee:

When I get to the Type.GetType(Globals.Settings.Store.ProviderType) in the CreateInstance Property the and check the value of the Globals.Settings.Store.ProviderType in the immediate window it says
Settings is not a member of Globals, even though all of the Globals.setting.Store properties are displayed in Intellisense.

Here is the contents of my Web.Config as it relates to these elements:

<configSections>
<sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensions SectionGroup, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
<sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGro up, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
<section name="scriptResourceHandler" type="System.Web.Configuration.ScriptingScriptReso urceHandlerSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="MachineToApplication"/>
<sectionGroup name="webServices" type="System.Web.Configuration.ScriptingWebService sSectionGroup, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
<section name="jsonSerialization" type="System.Web.Configuration.ScriptingJsonSerial izationSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="Everywhere"/>
<section name="profileService" type="System.Web.Configuration.ScriptingProfileSer viceSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="MachineToApplication"/>
<section name="authenticationService" type="System.Web.Configuration.ScriptingAuthentica tionServiceSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="false" allowDefinition="MachineToApplication"/>
</sectionGroup>
</sectionGroup>
</sectionGroup>

<section name="TheBMTStore" type="JG.BMTStore.TheBMTStoreSection"/>

</configSections>
<connectionStrings>
<add name="connBMT" connectionString="Data Source=seb2a54; Initial Catalog=BMTStore; User ID=BMTStoreUser; Password=atlas458" providerName="System.Data.SqlClient"/>
<add name="BMTStoreConnectionString" connectionString="Data Source=seb2a54;Initial Catalog=BMTStore;Integrated Security=True" providerName="System.Data.SqlClient"/>
</connectionStrings>

<appSettings>
<add key="connBMT.ConnectionString" value="Data Source=seb2a54;Initial Catalog=BMTStore;User ID=BMTStoreUser;Password=atlas458"/>
<add key="TheBMTStore.ConnectionString" value="Data Source=seb2a54;Initial Catalog=BMTStore;User ID=BMTStoreUser;Password=atlas458"/>
<add key="EnableCaching" value="true"/>
<add key="CacheDuration" value="600"/>
</appSettings>

<TheBMTStore defaultConnectionStringName="connBMT" >
<contactForm mailTo="Phi.eSupply.Request@ssa.gov"/>
<store businessEmail="Phi.eSupply.Request@ssa.gov" providerType="JG.BMTStore.DAL.SQLClient.SqlStorePr ovider" />
</TheBMTStore>

I added the providerType to the store element

Here is the Globals.vb Class:

Imports System.Web.Configuration
Imports Microsoft.VisualBasic
Namespace JG.BMTStore
Public NotInheritable Class Globals
Public Shared ReadOnly Settings As TheBMTStoreSection = _
CType(WebConfigurationManager.GetSection("TheBMTSt ore"), TheBMTStoreSection)

End Class

End Namespace

In the ConfigSection.vb I have Classes defined for the TheBMTStoreSection, ContactFormElement and the StoreElement and an empy class named ConfigSection. The StoreElement is built from the TheBMTStoreSection property store.

Can you spot anything that wrong?

Lee Dumond · February 16th, 2010, 05:23 PM

Well, one thing I see is that you're attempting to access Globals statically, but the Globals class is not marked as static (it's also sealed, which is a bit strange).

Try

Public Shared Class Globals

Jack Gillespie · February 16th, 2010, 05:33 PM

I tried the declare the Global class as "Public Shared" and get the message that "Classes can not be declared as Shared".

Lee Dumond · February 16th, 2010, 05:58 PM

Sorry, my VB is pretty rusty.

Jack Gillespie · February 17th, 2010, 09:10 AM

Lee:

Thanks for taking some much of your time to assist me.

You suggested hard coding the provider in the SqlstoreProvider.

"You will need to do that for this to work. Otherwise, if you don't require the ability to swap put providers, you could just hard-code the provider into the CreateInstance method."

I don't require the ability to swap providers.

I guess my question is how would you hard code the provider into the CreateInstance method?

I've tried several things here without success.

Lee Dumond · February 17th, 2010, 03:44 PM

Something like this... like I said, my VB is a tad rusty.

Code:

Public Shared ReadOnly Property Instance() As StoreProvider
 Get
  If _instance = Nothing Then
   _instance = CType(Activator.CreateInstance(Type.GetType("JG.BMTStore.DAL.SqlClient.SqlStoreProvider")), StoreProvider)
  End If
  Return _instance
 End Get
End Property