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How to pass variable from code behind to user control

I have been looking at several options in the knowledge base, however, have not found something that fits my needs. In my code behind "myWebControl.ascx.cs" I re-direct to a user control "myUC.cs". I want to pass a variable to the user control, possibly a session variable.

I know I can do "HttpContext.Current.Session["ServerName"] = psServerID;" in my code behind, however, don't know if this will be availabe to my UC after the re-direct. Note, the UC is just a .cs file (public class UserControl2 : System.Windows.Forms.UserControl)

Bob Learned

All session variables should be available as long as the current session is active, even with redirects.

Bob

66chawger

ASKER

Bob do you have an example? I attempted a session variable, but could not get it to work, which it should as you stated.

Bob Learned

Did you try something like this in the UserControl?

string serverName = Session["ServerName"].ToString();

Bob

66chawger

ASKER

So this is to retrieve it in the user control, correct?
To set the Session variable would be like what I have below using HttpContext:

HttpContext.Current.Session["ServerName"] = psServerID

Instead do:

Session("ServerName") = psServerID or
Session.ToString("ServerName") = psServerID ??

Bob Learned

Are you talking about VB.NET, because C# uses brackets, and VB.NET uses parentheses?

Session["ServerName"] = psServerID;

would work in a page code behind. ToString is a method for Object that converts the value to a string.

Bob

66chawger

ASKER

Bob, yes, C#...sorry!!!!! and as always end with a ";"....well depending! I know this is .NET 101, but I swear I tried this and I could not get my variable in the UC. Let me revisit and I will let you know.

66chawger

ASKER

Bob, this is what I am getting when building my the project that contains the UC we are discussing:

The UC is defined as:
public class UserControl2 : System.Windows.Forms.UserControl

The build error I receive is:

UserControl2.cs(40): The name 'Session' does not exist in the class or namespace 'PackageControl.UserControl2'

Am I missing a using statement, or is Session not available for a windows form usercontrol?

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Bob Learned

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66chawger

ASKER

Ok, then that was my initial issue... I can still value the session variable in the code behind without the fully qualified name as we discussed before. so session[blah blah in code behind and HttpContect.Current.Session in UC, correct?

66chawger

ASKER

Another Quality Expert!

66chawger

ASKER

Bob, I think I just had it in my head that the user control was being called as part of a re-direct and passing a variable to it. It was just brain "burp" if that makes any sense! Thanks again !

66chawger

ASKER

Bob, having a strange situation with httpcontext.
As we discussed previously, I used :

public string psServerName = HttpContext.Current.Session["ServerName"].ToString();

in my UC I needed to use the fully qualified name. What is happening is my UC is not instatiating. If it hits anything using httpcontext, the UC will not display, if I comment it out it displays. I tried this using httpcontext.current.response.write and same thing, anytime it runs into a statement with httpcontext, the UC will not load? Any ideas? All I am trying to do is what we discussed previously and that is retrieving the session variable in my UC.