Why I cannot access classes in .aspx codebehind from the classes in app_code in asp.net?

This is a fantastic problem that I faced. I was having a user control in my asp.net application as MSDD.ascx. I wanted to dynamically display this user control from the code written in the Dynamic.cs file in app_code folder of my applicaiton. But at this movement, I was unable to access the MSDD class written in codebehind file from my class in app_code. How can we proceed now???

Solution:

The best solution is to write an Interface. Place this interface in the app_code folder of you application. The aspx codebehind class should implment this particular interface. Now via interface you can access the codebehind class from you class in app_code folder. See the scenario below:

I have following files:

ASPX: A user control/class named MSDD.

app_code: A call named Dynamic, in which I want to access the above user control class MSDD.

Now write an interface IMSDD and make the codebehind class MSDD to implement this IMSDD interface. So you MSDD class will look like:

public class MSDD : IMSDD

{

// Code here...

}

And your Dynamic class which uses the Interface will look like:

public class Dynamic

{

IMSDDctrl = (IMSDD) Page.LoadControl("../MSDD.ascx");

// Now using this interface you can invoke any method/property of the MSDD class this is exposed via the interface.

ctrl.Invoke();

}

Hope this helps you...