private Table CreateTable()
{
       Table GroupedTable = new Table();
       GroupedTable.BorderWidth = Unit.Pixel(0);
       GroupedTable.CellPadding = 0;
       GroupedTable.CellSpacing = 0;
       GroupedTable.Style.Add(HtmlTextWriterStyle.Width, "100%");

   TableRow HeaderRow = new TableRow();
   TableCell HeaderCell = new TableCell();                    
   
   //Questo è il bottone che scatenerà l'evento
   ImageButton bottone = new ImageButton();
   bottone.ImageUrl = this.Page.ClientScript.GetWebResourceUrl(this.GetType(), "Resources.Images.Expand.gif");
   bottone .Attributes.Add("onclick", "javascript:HideShow('" + this._expandProcessListRow.ID + "');");
   
    HeaderCell.Controls.Add(this._imageButton) 
    HeaderRow.Cells.Add(HeaderCell);
    GroupedTable.Rows.Add(HeaderRow);

    // Aggiungo un testo alla riga da mostrare/nascondere
    TableCell processListCell = new TableCell();
    processListCell.Text = "PROVA";
    this._expandProcessListRow.Cells.Add(processListCell);

    worklistItemGroupedTable.Rows.Add(this._expandProcessListRow);
}