protected void OboutButton1_Click(object sender, EventArgs e)
{
    // Export current page
    ExportGridToPDF();
}

protected void OboutButton2_Click(object sender, EventArgs e)
{
    // Export all pages
    Grid1.PageSize = -1;
    Grid1.DataBind();
    ExportGridToPDF();
}

private void ExportGridToPDF()
{        
    // Stream which will be used to render the data
    MemoryStream fileStream = new MemoryStream();
        
    Document doc = new Document(iTextSharp.text.PageSize.LETTER, 10, 10, 42, 35);
    try
    {            
        //Create Document class object and set its size to letter and give space left, right, Top, Bottom Margin
        PdfWriter wri = PdfWriter.GetInstance(doc, fileStream);

        doc.Open();//Open Document to write

        Font font8 = FontFactory.GetFont("ARIAL", 7);

        //Write some content
        Paragraph paragraph = new Paragraph("ASP.NET Grid - Export to PDF");

        //Craete instance of the pdf table and set the number of column in that table
        PdfPTable PdfTable = new PdfPTable(Grid1.Columns.Count);
        PdfPCell PdfPCell = null;

        //Add headers of the pdf table
        foreach (Column col in Grid1.Columns)
        {                
            PdfPCell = new PdfPCell(new Phrase(new Chunk(col.HeaderText, font8)));
            PdfTable.AddCell(PdfPCell);
        }

        //How add the data from the Grid to pdf table
        for (int i = 0; i < Grid1.Rows.Count; i++)
        {
            Hashtable dataItem = Grid1.Rows[i].ToHashtable();

            foreach (Column col in Grid1.Columns)
            {
                PdfPCell = new PdfPCell(new Phrase(new Chunk(dataItem[col.DataField].ToString(), font8)));
                PdfTable.AddCell(PdfPCell);
            }
        }

        PdfTable.SpacingBefore = 15f;

        doc.Add(paragraph);
        doc.Add(PdfTable);
    }
    catch (DocumentException docEx)
    {
        //handle pdf document exception if any
    }
    catch (IOException ioEx)
    {
        // handle IO exception
    }
    catch (Exception ex)
    {
        // ahndle other exception if occurs
    }
    finally
    {
        //Close document and writer
        doc.Close();
    }

    // Send the data and the appropriate headers to the browser
    Response.Clear();
    Response.AddHeader("content-disposition", "attachment;filename=oboutGrid.pdf");
    Response.ContentType = "application/pdf";
    Response.BinaryWrite(fileStream.ToArray());
    Response.End(); 
}

Protected Sub OboutButton1_Click(ByVal sender As Object, ByVal e As EventArgs)
    ' Export current page
    ExportGridToPDF()
End Sub

Protected Sub OboutButton2_Click(ByVal sender As Object, ByVal e As EventArgs)
    ' Export all pages
    Grid1.PageSize = -1
    Grid1.DataBind()
    ExportGridToPDF()
End Sub

Private Sub ExportGridToPDF()
    ' Stream which will be used to render the data
    Dim fileStream As MemoryStream = New MemoryStream()

    Dim doc As Document = New Document(iTextSharp.text.PageSize.LETTER, 10, 10, 42, 35)

    Try
        ' Create Document class object and set its size to letter and give space left, right, Top, Bottom Margin
        Dim wri As PdfWriter = PdfWriter.GetInstance(doc, fileStream)

        doc.Open() ' Open Document to write

        Dim font8 As Font = FontFactory.GetFont("ARIAL", 7)

        ' Write some content
        Dim paragraph As Paragraph = New Paragraph("ASP.NET Grid - Export to PDF")

        'Craete instance of the pdf table and set the number of column in that table
        Dim PdfTable As PdfPTable = New PdfPTable(Grid1.Columns.Count)
        Dim PdfPCell As PdfPCell = Nothing

        ' Add headers of the pdf table
        For Each col As Column In Grid1.Columns
            PdfPCell = New PdfPCell(New Phrase(New Chunk(col.HeaderText, font8)))
            PdfTable.AddCell(PdfPCell)
        Next

        ' How add the data from the Grid to pdf table
        For i As Integer = 0 To Grid1.Rows.Count - 1
            Dim dataItem As Hashtable = Grid1.Rows(i).ToHashtable()

            For Each col As Column In Grid1.Columns

                PdfPCell = New PdfPCell(New Phrase(New Chunk(dataItem(col.DataField).ToString(), font8)))
                PdfTable.AddCell(PdfPCell)
            Next
        Next i

        PdfTable.SpacingBefore = 15.0F

        doc.Add(paragraph)
        doc.Add(PdfTable)
    Catch docEx As DocumentException
        ' handle pdf document exception if any        
    Catch ioEx As IOException
        ' handle IO exception        
    Catch ex As Exception
        ' ahndle other exception if occurs        
    Finally
        ' Close document and writer
        doc.Close()
    End Try

    ' Send the data and the appropriate headers to the browser
    Response.Clear()
    Response.AddHeader("content-disposition", "attachment;filename=oboutGrid.pdf")
    Response.ContentType = "application/pdf"
    Response.BinaryWrite(fileStream.ToArray())
    Response.End()
End Sub