How to create Header and Footer in PDF document?

Hello, when there are multiple pages, how can I show the footer on the last page? I try like this;

  private async void ToolbarItem_Clicked(object sender, EventArgs e)
  {

            DataGridPdfExportingController pdfExport = new DataGridPdfExportingController();
            pdfExport.HeaderAndFooterExporting += PdfExport_HeaderAndFooterExporting;

            MemoryStream stream = new MemoryStream();
            var exportToPdf = pdfExport.ExportToPdf(this.dataGrid, new DataGridPdfExportOption()
            {
                FitAllColumnsInOnePage = true,
                ExportColumnWidth = true,
                ApplyGridStyle = true,

            });            
                PdfPageTemplateElement footer = AddFooter(exportToPdf);
                exportToPdf.Pages[exportToPdf.Pages.Count - 1].Section.Template.ApplyDocumentBottomTemplate = true;
                exportToPdf.Pages[exportToPdf.Pages.Count - 1].Section.Template.Bottom = footer; 
                exportToPdf.Save(stream);
                exportToPdf.Close(true);
}
        public PdfPageTemplateElement AddFooter(PdfDocument doc)
        {
            float Width = doc.Pages[0].GetClientSize().Width;          

            PdfPageTemplateElement footer = new PdfPageTemplateElement(Width, 220);

            return footer;
        }
        private void PdfExport_HeaderAndFooterExporting(object sender, PdfHeaderFooterEventArgs e)
        {

            float Width = e.PdfPage.GetClientSize().Width;
            PdfPageTemplateElement header = new PdfPageTemplateElement(Width, 225);
e.PdfDocumentTemplate.Top = header;

but didn't work