Question

I have a base control:

public partial class BaseControl : System.Web.UI.UserControl
{
    protected virtual void Page_Load(object sender, EventArgs e)
    {
    }

    protected override void OnInit(EventArgs e)
    {
        base.OnInit(e);
        Page.LoadComplete += Page_LoadComplete;
    }

    protected virtual void Page_LoadComplete(object sender, EventArgs e)
    {
        Page.LoadComplete -= Page_LoadComplete;
    }
}

I then have a control that derives from this

public partial class MyChildControl : BaseControl

The problem I have is that if I load MyChildControl more than once then I get an object ref error on Page.LoadComplete -= Page_LoadComplete; in BaseControl. I sort of understand why but I have 2 questions:

1. Shouldn’t each MyChildControl reference it’s own version of BaseControl which in turn registers it’s own PageLoadComplete?
2. How can I check to see if it is not null? I can’t seem to do != null.

EDIT: It seems that Page is null and checking Page != null resolves the issue but I still don’t understand how Page is null.

Answer 1

Page_LoadComplete can’t be null, it’s just a delegate created for methog Page_LoadComplete. So i think Page in Page.LoadComplete may be null or page has custom logic for adding handler to event LoadComplete and has ref error there