using System;
using System.IO;
using System.Text;
using System.Collections;
namespace PDFGenerator
{
  public class PDFGenerator
  {
    static float pageWidth = 594.0f;
    static float pageDepth = 828.0f;
    static float pageMargin = 30.0f;
    static float fontSize = 20.0f;
    static float leadSize = 10.0f;
    static StreamWriter pPDF = new StreamWriter("E:\\myPDF.pdf");
    static MemoryStream mPDF = new MemoryStream();
    static void ConvertToByteAndAddtoStream(string strMsg)
    {
      Byte[] buffer = null;
      buffer = ASCIIEncoding.ASCII.GetBytes(strMsg);
      mPDF.Write(buffer, 0, buffer.Length);
      buffer = null;
    }
    static string xRefFormatting(long xValue)
    {
      string strMsg = xValue.ToString();
      int iLen = strMsg.Length;
      if (iLen < 10)
      {
        StringBuilder s = new StringBuilder();
        int i = 10 - iLen;
        s.Append('0', i);
        strMsg = s.ToString() + strMsg;
      }
      return strMsg;
    }
    static void Main(string[] args)
    {
      ArrayList xRefs = new ArrayList();
      //Byte[] buffer=null;
      float yPos = 0f;
      long streamStart = 0;
      long streamEnd = 0;
      long streamLen = 0;
      string strPDFMessage = null;
      //PDF文檔頭信息
      strPDFMessage = "%PDF-1.1\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      xRefs.Add(mPDF.Length);
      strPDFMessage = "1 0 obj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "<< /Length 2 0 R >>\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "stream\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      ////////PDF文檔描述
      streamStart = mPDF.Length;
      //字體
      strPDFMessage = "BT\n/F0 " + fontSize + " Tf\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      //PDF文檔實體高度
      yPos = pageDepth - pageMargin;
      strPDFMessage = pageMargin + " " + yPos + " Td\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = leadSize + " TL\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      //實體內容
      strPDFMessage = "(http://www.wenhui.org)Tj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "ET\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      streamEnd = mPDF.Length;
      streamLen = streamEnd - streamStart;
      strPDFMessage = "endstream\nendobj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      //PDF文檔的版本信息
      xRefs.Add(mPDF.Length);
      strPDFMessage = "2 0 obj\n" + streamLen + "\nendobj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      xRefs.Add(mPDF.Length);
      strPDFMessage = "3 0 obj\n<</Type/Page/Parent 4 0 R/Contents 1 0 R>>\nendobj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      xRefs.Add(mPDF.Length);
      strPDFMessage = "4 0 obj\n<</Type /Pages /Count 1\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "/Kids[\n3 0 R\n]\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "/Resources<</PRocSet[/PDF/Text]/Font<</F0 5 0 R>> >>\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "/MediaBox [ 0 0 " + pageWidth + " " + pageDepth + " ]\n>>\nendobj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      xRefs.Add(mPDF.Length);
      strPDFMessage = "5 0 obj\n<</Type/Font/Subtype/Type1/BaseFont/Courier/Encoding/WinAnsiEncoding>>\nendobj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      xRefs.Add(mPDF.Length);
      strPDFMessage = "6 0 obj\n<</Type/Catalog/Pages 4 0 R>>\nendobj\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      streamStart = mPDF.Length;
      strPDFMessage = "xref\n0 7\n0000000000 65535 f \n";
      for (int i = 0; i < xRefs.Count; i++)
      {
        strPDFMessage += xRefFormatting((long)xRefs[i]) + " 00000 n \n";
      }
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "trailer\n<<\n/Size " + (xRefs.Count + 1) + "\n/Root 6 0 R\n>>\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      strPDFMessage = "startxref\n" + streamStart + "\n%%EOF\n";
      ConvertToByteAndAddtoStream(strPDFMessage);
      mPDF.WriteTo(pPDF.BaseStream);
      mPDF.Close();
      pPDF.Close();
    }
  }
}