//write by wenhui.org
using System;
using System.IO;
using System.Text;
using System.Collections;

namespace PDFGenerator
{

public class PDFGenerator
{
static float pageWidth = 9.0f;
static float pageDepth = 88.0f;
static float pageMargin = 0.0f;
static float fontSize = 0.0f;
static float leadSize = 0.0f;


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<0)
{
StringBuilder s=new StringBuilder();
int i=0-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文档头信息
strPDFMessage="％PDF-.\n";
ConvertToByteAndAddtoStream(strPDFMessage);

xRefs.Add(mPDF.Length);
strPDFMessage=" 0 obj\n";
ConvertToByteAndAddtoStream(strPDFMessage);
strPDFMessage="<< /Length 0 R >>\n";
ConvertToByteAndAddtoStream(strPDFMessage);
strPDFMessage="stream\n";
ConvertToByteAndAddtoStream(strPDFMessage);
/**/////////PDF文档描述
streamStart=mPDF.Length;
//字体
strPDFMessage="BT\n/F0 " + fontSize +" Tf\n";
ConvertToByteAndAddtoStream(strPDFMessage);
//PDF文档实体高度
yPos = pageDepth - pageMargin;
strPDFMessage=pageMargin + " " + yPos +" Td\n" ;
ConvertToByteAndAddtoStream(strPDFMessage);
strPDFMessage= leadSize+" TL\n" ;
ConvertToByteAndAddtoStream(strPDFMessage);

//实体内容
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文档的版本信息
xRefs.Add(mPDF.Length);
strPDFMessage=" 0 obj\n"+ streamLen + "\nendobj\n";
ConvertToByteAndAddtoStream(strPDFMessage);

xRefs.Add(mPDF.Length);
strPDFMessage=" 0 obj\n<</Type/Page/Parent 0 R/Contents 0 R>>\nendobj\n";
ConvertToByteAndAddtoStream(strPDFMessage);

xRefs.Add(mPDF.Length);
strPDFMessage=" 0 obj\n<</Type /Pages /Count \n";
ConvertToByteAndAddtoStream(strPDFMessage);
strPDFMessage="/Kids[\n 0 R\n]\n";
ConvertToByteAndAddtoStream(strPDFMessage);
strPDFMessage="/Resources<</ProcSet[/PDF/Text]/Font<</F0 0 R>> >>\n";
ConvertToByteAndAddtoStream(strPDFMessage);
strPDFMessage="/MediaBox [ 0 0 "+ pageWidth + " " + pageDepth + " ]\n>>\nendobj\n";
ConvertToByteAndAddtoStream(strPDFMessage);

xRefs.Add(mPDF.Length);
strPDFMessage=" 0 obj\n<</Type/Font/Subtype/Type/BaseFont/Courier/Encoding/WinAnsiEncoding>>\nendobj\n";
ConvertToByteAndAddtoStream(strPDFMessage);

xRefs.Add(mPDF.Length);
strPDFMessage="6 0 obj\n<</Type/Catalog/Pages 0 R>>\nendobj\n";
ConvertToByteAndAddtoStream(strPDFMessage);

streamStart=mPDF.Length;
strPDFMessage="xref\n0 7\n0000000000 6 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+)+"\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();
}
}
}