When placeholder is filled with content from page in master page

Question

My question about the placeholder, basically I have to perfrom a check in my custom user control for some controls, but does controls are loaded from a page in a placeholder.

And my user is located on the master page of course.

So in a user control I wrote something like this:

        protected void Page_Load(object sender, EventArgs e)
        {
            this.Page.LoadComplete += new EventHandler(Page_LoadComplete);
        }

        void Page_LoadComplete(object sender, EventArgs e)
        {
             //looping thru all the controls in the page
        }

So basically i call a method on page load complete, BUT I don't find the control which I'm looking for, so my question WHEN do the place holders are beeing loaded with the contenct from pages?

How can I get access to controls of those pages from master page, when are they available?

Answer 1

There is probably one of two things going on here:

1. Your Page Load Event is getting called before the Master Page event.
2. Your control is in a naming container that's buried in your control tree.

To solve item 2, you could create a recursive method that walks the control tree. But this is pretty expensive, especially if the control is not found.

private static Control FindControlRecursive(Control Root, string Id) 
{
    if (Root.ID == Id) 
    return Root; 

    foreach (Control Ctl in Root.Controls) 
    {
        Control FoundCtl = FindControlRecursive(Ctl, Id); 
        if (FoundCtl != null) 
            return FoundCtl; 
    }
    return null; 
}

If you know how deep the control is, you can do .FindControl().FindControl.FindControl() etc. But this is fragile.

I recently saw someone (Popa D. Stelian) use a linked list for this. I thought this was an interesting approach:

private static Control FindControlIterative(Control root, string id) 
{ 
    Control ctl = root; 
    LinkedList ctls = new LinkedList(); 

    while (ctl != null) 
    { 
        if (ctl.ID == id) 
            return ctl; 
        foreach (Control child in ctl.Controls) 
        { 
            if (child.ID == id) 
                return child; 
            if (child.HasControls()) 
                ctls.AddLast(child); 
        } 
        ctl = ctls.First.Value; 
        ctls.Remove(ctl); 
    } 
    return null; 
}

Regards, Mike Sharp