protected void btnAddPage_Click(object sender, EventArgs e)
{
PageInfo page = Pages.FindPage(lstAvailablePage.SelectedValue);
PageContent content = Content.GetPageContent(page, false);
lstPages.Items.Add(new ListItem(FormattingPipeline.PrepareTitle(content.Title, false, FormattingContext.Other, page), page.FullName));
lstAvailablePage.Items.RemoveAt(lstAvailablePage.SelectedIndex);
btnAddPage.Enabled = lstAvailablePage.Items.Count > 0;
}