Class not found in ASP.NET project

Please forgive me, I'm new to C#.

I have added a class file to my ASP.NET project but I cannot reference it as a type in my default.aspx code behind.  

I've put test classes at the root of the project and in folders under App_Code.  All the types I try to declare error out on compile.

What steps do I need to take after creating a class file to be able to reference that class in the rest of my app?

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CyrexCore2kConnect With a Mentor Commented:
Look at your classes and note their namespace in relation to the namespace of your default.aspx page class. It's probably going to be something like

namespace xxxxYourProjectNamexxxx.App_Code // for the classes
namespace xxxxYourProjectNamexxxx // for the page

So to reference an class from your page you're going to either have to write


or add a using statement:

using xxxxYourProjectNamexxxx.App_Code;

to the top of your code behind file
CuteBugConnect With a Mentor Commented:
You need to add a reference of the dll to which this class belongs.
BruceAuthor Commented:
My new class is not within a namespace.  The class I am tying to reference is actually imported from another project where it was being used without a namespace declaration.

Is this a case of I have to either "Add Reference" to a DLL or wrap the class within a namespace in order to be referenced?  

If I do the "Add Reference" on a class that exists only within my project where do I find the DLL on my file structure in order to reference it.
BruceAuthor Commented:
I added the namespace to my class at the root of the project and that gets referenced.  But the class that is in my App_Code directory is still not showing.  The specific location of the class file I am trying to reference is ~/App_Code/Common/ActiveDirectoryHelper.cs.

I have tried wrapping these namespaces around the ActiveDirectoryHelper class declaration

After each I tried a rebuild and then tried to dot operate off the AppSurvey_PType namespace but App_Code does not show under there...

Is this where I need to somehow build a DLL for the class file and reference it or can I still try to use namespace to reference it?

BruceAuthor Commented:
This was a tough one so I just started a new Web Project in Visual Studio.  There was something not set right on the "solution" because when I tried to add Web Forms it would not show the options for selecting a master page.

I've added the my existing file from the other project, then added the namespace in those class files and they all show up when I dot operate in the code behind.

Thanks for you help!  I don't know what is different between the projects but starting a new one and adding my work back in was the workaround.
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