Question

Say aspx page called theParent has a DataGrid control named theDataGrid and a UserControl named theUserControl , and theUserControl has a button named theUcButton .

Yes, I know, very imaginative naming.

When theUcButton is clicked , a session variable is changed.

This session variable is a select parameter for the datasource of theDataGrid.

However, because of the order of stuff called in the page lifecycle, when theUcButton is clicked and a postback is generated ,
theParent controls are loaded before theUserControl resets the session variable, and theDataGrid does not show the new data until the next postback .

How to I get what I want to work?

I am using 3.5 if that matters.

Answer 1

Here is example code for your user control to raise an event.

public partial class WebUserControl : System.Web.UI.UserControl{
public event EventHandler Updated;

protected void Button1_Click(object sender, EventArgs e)
{
    //do some work to this user control

    //raise the Updated event
    if (Updated != null)
        Updated(sender, e);
}}

Then from your .aspx page, you’ll deal with the new event just like usual

    <uc1:WebUserControl ID="WebUserControl1" runat="server" OnUpdated="WebUserControl1_Updated" />

Code behind:

protected void WebUserControl1_Updated(object sender, EventArgs e)
{
    //handle the user control event
}