asp.net dynamically added user control saving values after postback

Question

Here\'s my issue. I have a usercontrol that I want to allow users to add as many instances of as necessary using a button click (each time a button is clicked, I want to ad

Answer 1

It's an ugly solution if you have a ton of users, but you could stick the usercontrols themselves into the session. I do this with my footer control because I don't want to hit the db every time the page changes to recreate the footer.

This solutions can get really tasking on the server if you have a lot of users and they use this feature a lot. At least I think it will...

But you can just repopulate your placeholder that has the usercontrols in it on page_load. I can put up an example shortly.

Example of what I do:

if (Session["footer"] == null)
{
 Session["footer"] = new Footer(LinksRules.BuildFooterLinks((int)WebSiteSections.Main));// where Footer is my control
}
footerPH.Controls.Add((Footer)Session["footer"]);

Like a singleton pattern sort of...

So as I see it you could do this on anything that will cause a postback

Session["DynamicControls"] = PlaceHolder.Controls;

and in the page-Load method you could:

foreach(var control in (List)Session["DynamicControls"])
{
  yourPlaceHolder.Controls.Add(control);
}

and if the session object is null just add a single one like they've never been there..

I believe this will hang on to the data inside the controls like you want.