改变itextsharp表格的字体大小

我试图使用iTextSharp查看PDF文件中的表。我已经知道如何添加表格，并使PDF文件打开一个按钮点击，但表格字体太大，文字被包裹，使他们难以阅读。我输入了这个代码，但是表格的字体没有任何变化。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlServerCe;
using System.IO;
using iTextSharp.text;
using iTextSharp.text.pdf;
namespace Lewis_Warby_Airbrushing
{
    public partial class selectedorderForm : Form
    {
        public selectedorderForm(string strValue)
        {
            InitializeComponent();
            textBox1.Text = strValue;
        }
        DataTable dt;
        private void selectedorderForm_Load(object sender, EventArgs e)
        {
            SqlCeConnection con = new SqlCeConnection(@"Data Source=|DataDirectory|'LWADataBase.sdf;");
            SqlCeDataAdapter sda = new SqlCeDataAdapter("select * from orderTBL ", con);
            dt = new DataTable();
            sda.Fill(dt);
            dataGridView1.DataSource = dt;
            DataView dv = new DataView(dt);
            dv.RowFilter = "[Order Number] like '%" + textBox1.Text.Trim() + "%'";
            dataGridView1.DataSource = dv;
        }
        private void pdfBTN_Click(object sender, EventArgs e)
        {
            iTextSharp.text.Font fontTitle = FontFactory.GetFont("Arial", 18, iTextSharp.text.Font.BOLD, BaseColor.BLACK);

            Document doc = new Document(iTextSharp.text.PageSize.A4, 10, 10, 10, 10);

            PdfWriter wri = PdfWriter.GetInstance(doc, new FileStream("PurchaseOrder-"+textBox1.Text+".pdf", FileMode.Create));
            doc.Open();

            Paragraph title = new Paragraph("PURCHASE ORDER " + textBox1.Text +"'n Lewis Warby Airbrushing'n", fontTitle);
            title.Alignment = Element.ALIGN_CENTER;
            doc.Add(title);
            title.SpacingAfter = 15f;



            iTextSharp.text.Font fontTable = FontFactory.GetFont("Arial", 5, iTextSharp.text.Font.NORMAL, BaseColor.BLACK);
            PdfPTable table = new PdfPTable(dataGridView1.Columns.Count);
            table.SpacingBefore = 45f;
            table.TotalWidth = 216f;
            table.DefaultCell.Phrase = new Phrase() { Font = fontTable };
            for (int j = 0; j < dataGridView1.Columns.Count; j++)
            {
                table.AddCell(new Phrase(dataGridView1.Columns[j].HeaderText));
            }
            table.HeaderRows = 1;
            for (int i = 0; i < dataGridView1.Rows.Count; i++)
            {
                for (int k = 0; k < dataGridView1.Columns.Count; k++)
                {
                    if (dataGridView1[k, i].Value != null)
                    {
                        table.AddCell(new Phrase(dataGridView1[k, i].Value.ToString()));
                    }
                }
            }

            doc.Add(table);


            doc.Close();
            System.Diagnostics.Process.Start("PurchaseOrder-"+textBox1.Text+".pdf");

        }
    }
}

for (int j = 0; j < dataGridView1.Columns.Count; j++)
{
    table.AddCell(new Phrase(dataGridView1.Columns[j].HeaderText,fontTable));
}
//..
for (int i = 0; i < dataGridView1.Rows.Count; i++)
{
    for (int k = 0; k < dataGridView1.Columns.Count; k++)
    {
         if (dataGridView1[k, i].Value != null)
         {
              table.AddCell(new Phrase(dataGridView1[k, i].Value.ToString(),fontTable));
         }
     }
}