C#利用iTextSharp实现给PDF添加条形码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

using iTextSharp;
using iTextSharp.text;
using iTextSharp.text.pdf;

namespace PDFWatermark
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                AddMark();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }

        private static void AddMark()
        {
            try
            {
                BarCodeDrawing _Code39 = new BarCodeDrawing();
                _Code39.Height = 50;
                _Code39.Magnify = 1;
                _Code39.ViewFont = new System.Drawing.Font("宋体", 13);
                System.Drawing.Image _codeImage = _Code39.GetCodeImage("2013121542", BarCodeDrawing.BarCodeDrawingModel.BarCodeDrawingNormal, true);
                System.IO.MemoryStream _Stream = new System.IO.MemoryStream();
                _codeImage.Save(_Stream, System.Drawing.Imaging.ImageFormat.Jpeg);

                string markPath = System.Environment.CurrentDirectory + "/temp.jpg";
                _codeImage.Save(markPath);

                string sourcePdfPath = @"D:\01项目\14建设工程造价管理系统\PMCostStation\CostStation\uploads\contract\7a720e8f-d267-4503-87d6-8ec62aecd3aa.pdf";
                sourcePdfPath = System.Environment.CurrentDirectory + "/a.pdf";
                string outputPdfPath = @"D:\01项目\14建设工程造价管理系统\PMCostStation\CostStation\uploads\contract\7a720e8f-d267-4503-87d6-8ec62aecd3aa.pdf";
                outputPdfPath = System.Environment.CurrentDirectory + "/b.pdf";
                markPath = @"D:\01项目\14建设工程造价管理系统\PMCostStation\CostStation\uploads/2013121861450.jpg";

                float imgWidth = 200 * 72 / 96;
                float imgHeight = 30 * 72 / 96;

                AddPDFWaterMark(sourcePdfPath, outputPdfPath, markPath, imgWidth, imgHeight);
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                //document.Close();
            }
        }

        private static void AddPDFWaterMark(string sourcePdfPath, string outputPdfPath, string imgPath, float imgWidth, float imgHeight)
        {
            PdfReader reader = null;
            PdfStamper stamper = null;

            try
            {
                reader = new PdfReader(sourcePdfPath);
                stamper = new PdfStamper(reader, new FileStream(outputPdfPath, FileMode.Create));

                Rectangle psize = reader.GetPageSize(1);
                float positionX = psize.Width - imgWidth;
                float positionY = psize.Height - imgHeight;             

                int n = reader.NumberOfPages;
                int i = 0;
                PdfContentByte under;
                iTextSharp.text.Image im = iTextSharp.text.Image.GetInstance(imgPath);                
                im.SetAbsolutePosition(positionX, positionY);                
                im.ScaleAbsolute(imgWidth, imgHeight);    
                
                while (i < n)
                {
                    i++;
                    under = stamper.GetUnderContent(i);                      
                    under.AddImage(im);
                }
                stamper.Close();
                reader.Close();                
            }
            catch (Exception ex)
            {
                //PMApplicationLog.WriteError(ex, "", null);
                //throw new PMException("PDF添加水印时发生错误");
                throw ex;
            }
            finally
            {
                if (reader != null)
                {
                    reader.Close();
                }
                if (stamper != null)
                {
                    stamper.Close();
                }
            }
        }
    }
}

　　

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Collections;

namespace PDFWatermark
{
    /// <summary>
    /// 绘制条形码图形
    /// </summary>
    public class BarCodeDrawing
    {
        private Hashtable m_BarCodeDrawing = new Hashtable();

        private byte m_Magnify = 0;
        /// <summary>
        /// 放大倍数
        /// </summary>
        public byte Magnify { get { return m_Magnify; } set { m_Magnify = value; } }

        private int m_Height = 40;
        /// <summary>
        /// 图形高
        /// </summary>
        public int Height { get { return m_Height; } set { m_Height = value; } }

        private Font m_ViewFont = null;
        /// <summary>
        /// 字体大小
        /// </summary>
        public Font ViewFont { get { return m_ViewFont; } set { m_ViewFont = value; } }



        public BarCodeDrawing()
        {

            m_BarCodeDrawing.Add("A", "1101010010110");
            m_BarCodeDrawing.Add("B", "1011010010110");
            m_BarCodeDrawing.Add("C", "1101101001010");
            m_BarCodeDrawing.Add("D", "1010110010110");
            m_BarCodeDrawing.Add("E", "1101011001010");
            m_BarCodeDrawing.Add("F", "1011011001010");
            m_BarCodeDrawing.Add("G", "1010100110110");
            m_BarCodeDrawing.Add("H", "1101010011010");
            m_BarCodeDrawing.Add("I", "1011010011010");
            m_BarCodeDrawing.Add("J", "1010110011010");
            m_BarCodeDrawing.Add("K", "1101010100110");
            m_BarCodeDrawing.Add("L", "1011010100110");
            m_BarCodeDrawing.Add("M", "1101101010010");
            m_BarCodeDrawing.Add("N", "1010110100110");
            m_BarCodeDrawing.Add("O", "1101011010010");
            m_BarCodeDrawing.Add("P", "1011011010010");
            m_BarCodeDrawing.Add("Q", "1010101100110");
            m_BarCodeDrawing.Add("R", "1101010110010");
            m_BarCodeDrawing.Add("S", "1011010110010");
            m_BarCodeDrawing.Add("T", "1010110110010");
            m_BarCodeDrawing.Add("U", "1100101010110");
            m_BarCodeDrawing.Add("V", "1001101010110");
            m_BarCodeDrawing.Add("W", "1100110101010");
            m_BarCodeDrawing.Add("X", "1001011010110");
            m_BarCodeDrawing.Add("Y", "1100101101010");
            m_BarCodeDrawing.Add("Z", "1001101101010");
            m_BarCodeDrawing.Add("0", "1010011011010");
            m_BarCodeDrawing.Add("1", "1101001010110");
            m_BarCodeDrawing.Add("2", "1011001010110");
            m_BarCodeDrawing.Add("3", "1101100101010");
            m_BarCodeDrawing.Add("4", "1010011010110");
            m_BarCodeDrawing.Add("5", "1101001101010");
            m_BarCodeDrawing.Add("6", "1011001101010");
            m_BarCodeDrawing.Add("7", "1010010110110");
            m_BarCodeDrawing.Add("8", "1101001011010");
            m_BarCodeDrawing.Add("9", "1011001011010");
            m_BarCodeDrawing.Add("+", "1001010010010");
            m_BarCodeDrawing.Add("-", "1001010110110");
            m_BarCodeDrawing.Add("*", "1001011011010");
            m_BarCodeDrawing.Add("/", "1001001010010");
            m_BarCodeDrawing.Add("%", "1010010010010");
            m_BarCodeDrawing.Add("contentquot", "1001001001010");
            m_BarCodeDrawing.Add(".", "1100101011010");
            m_BarCodeDrawing.Add(" ", "1001101011010");

        }


        public enum BarCodeDrawingModel
        {
            /// <summary>
            /// 基本类别 1234567890ABC
            /// </summary>
            BarCodeDrawingNormal,
            /// <summary>
            /// 全ASCII方式 +A+B 来表示小写
            /// </summary>
            BarCodeDrawingFullAscII
        }
        /// <summary>
        /// 获得条码图形
        /// </summary>
        /// <param name="p_Text">文字信息</param>
        /// <param name="p_Model">类别</param>
        /// <param name="p_StarChar">是否增加前后*号</param>
        /// <returns>图形</returns>
        public Bitmap GetCodeImage(string p_Text, BarCodeDrawingModel p_Model, bool p_StarChar)
        {
            string _ValueText = "";
            string _CodeText = "";
            char[] _ValueChar = null;
            switch (p_Model)
            {
                case BarCodeDrawingModel.BarCodeDrawingNormal:
                    _ValueText = p_Text.ToUpper();
                    break;
                default:
                    _ValueChar = p_Text.ToCharArray();
                    for (int i = 0; i != _ValueChar.Length; i++)
                    {
                        if ((int)_ValueChar[i] >= 97 && (int)_ValueChar[i] <= 122)
                        {
                            _ValueText += "+" + _ValueChar[i].ToString().ToUpper();

                        }
                        else
                        {
                            _ValueText += _ValueChar[i].ToString();
                        }
                    }
                    break;
            }


            _ValueChar = _ValueText.ToCharArray();

            if (p_StarChar == true) _CodeText += m_BarCodeDrawing["*"];

            for (int i = 0; i != _ValueChar.Length; i++)
            {
                if (p_StarChar == true && _ValueChar[i] == '*') throw new Exception("带有起始符号不能出现*");

                object _CharCode = m_BarCodeDrawing[_ValueChar[i].ToString()];
                if (_CharCode == null) throw new Exception("不可用的字符" + _ValueChar[i].ToString());
                _CodeText += _CharCode.ToString();
            }


            if (p_StarChar == true) _CodeText += m_BarCodeDrawing["*"];


            Bitmap _CodeBmp = GetImage(_CodeText);
            GetViewImage(_CodeBmp, p_Text);
            return _CodeBmp;
        }



        /// <summary>
        /// 绘制编码图形
        /// </summary>
        /// <param name="p_Text">编码</param>
        /// <returns>图形</returns>
        private Bitmap GetImage(string p_Text)
        {
            char[] _Value = p_Text.ToCharArray();


            //宽 == 需要绘制的数量*放大倍数 + 两个字的宽   
            Bitmap _CodeImage = new Bitmap(_Value.Length * ((int)m_Magnify + 1), (int)m_Height);
            Graphics _Garphics = Graphics.FromImage(_CodeImage);

            _Garphics.FillRectangle(Brushes.White, new Rectangle(0, 0, _CodeImage.Width, _CodeImage.Height));

            int _LenEx = 0;
            for (int i = 0; i != _Value.Length; i++)
            {
                int _DrawWidth = m_Magnify + 1;
                if (_Value[i] == '1')
                {
                    _Garphics.FillRectangle(Brushes.Black, new Rectangle(_LenEx, 0, _DrawWidth, m_Height));

                }
                else
                {
                    _Garphics.FillRectangle(Brushes.White, new Rectangle(_LenEx, 0, _DrawWidth, m_Height));
                }
                _LenEx += _DrawWidth;
            }



            _Garphics.Dispose();
            return _CodeImage;
        }
        /// <summary>
        /// 绘制文字
        /// </summary>
        /// <param name="p_CodeImage">图形</param>
        /// <param name="p_Text">文字</param>
        private void GetViewImage(Bitmap p_CodeImage, string p_Text)
        {
            if (m_ViewFont == null) return;
            Graphics _Graphics = Graphics.FromImage(p_CodeImage);
            SizeF _FontSize = _Graphics.MeasureString(p_Text, m_ViewFont);

            if (_FontSize.Width > p_CodeImage.Width || _FontSize.Height > p_CodeImage.Height - 20)
            {
                _Graphics.Dispose();
                return;
            }
            int _StarHeight = p_CodeImage.Height - (int)_FontSize.Height;

            _Graphics.FillRectangle(Brushes.White, new Rectangle(0, _StarHeight, p_CodeImage.Width, (int)_FontSize.Height));

            int _StarWidth = (p_CodeImage.Width - (int)_FontSize.Width) / 2;

            _Graphics.DrawString(p_Text, m_ViewFont, Brushes.Black, _StarWidth, _StarHeight);

            _Graphics.Dispose();

        }
    }
}

　　需要引用itextsharp.dll