用C#代码生成一个简单的PDF文件

摘自《程序员大本营2001.net版》

using System;
using System.IO;
using System.Text;
using System.Collections;

namespace PDFGenerator
{
    /// <summary>
    /// Application : Generation of PDF file from text
    /// Author        : Pramod Kumar Singh
    /// Date        : 25th July 2001
    ///</summary>
        
    public class PDFGenerator
    {
        static float pageWidth = 594.0f;
        static float pageDepth = 828.0f;
        static float pageMargin = 30.0f;
        static float fontSize = 10.0f;
        static float leadSize = 10.0f;
        
        //Create a PDF file.
        //PDF on Disk
        static StreamWriter pPDF=new StreamWriter("F://Temp//myPDF.pdf");
        //PDF in Memory
        static MemoryStream mPDF= new MemoryStream();
        
        //Convert the Text Data to PDF format and write back to
        //Memory Stream
        static void ConvertToByteAndAddtoStream(string strMsg)
        {
            Byte[] buffer=null;
            buffer=ASCIIEncoding.ASCII.GetBytes(strMsg);
            mPDF.Write(buffer,0,buffer.Length);  
            buffer=null;
        }
        
        //Format the data length in xRef Format
        static string xRefFormatting(long xValue)
        {
            string strMsg =xValue.ToString();
            int iLen=strMsg.Length;
            if (iLen<10)
            {
                StringBuilder s=new StringBuilder();
                //string s=null;
                int i=10-iLen;
                s.Append('0',i);
                strMsg=s.ToString() + strMsg;
            }
            return strMsg;
        }

        //Entry Point
        static void Main(string[] args)
        {
            //Create a ArrayList for xRefs of PDF Document
            ArrayList xRefs=new ArrayList();
            Byte[] buffer=null;
            float yPos =0f;
            long streamStart=0;
            long streamEnd=0;
            long streamLen =0;
            string strPDFMessage=null;
            //PDF Header Message
            strPDFMessage="%PDF-1.1/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            
            //ID 1 For Containt
            //ID 2 For Length of the Stream
            //write the Text
            
            //1> Start a new Page
            xRefs.Add(mPDF.Length);
            strPDFMessage="1 0 obj/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            strPDFMessage="<< /Length 2 0 R >>/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            strPDFMessage="stream/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            
            //Get the start of the stream
            streamStart=mPDF.Length;
            strPDFMessage="BT/n/F0 " + fontSize +" Tf/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            yPos = pageDepth - pageMargin;
            strPDFMessage=pageMargin + " " + yPos +" Td/n" ;
            ConvertToByteAndAddtoStream(strPDFMessage);
            strPDFMessage= leadSize+" TL/n" ;
            ConvertToByteAndAddtoStream(strPDFMessage);
            
            //Add the text data to the PDF memory stream
            strPDFMessage= "(Pramod Kumar Singh)Tj/n" ;
            ConvertToByteAndAddtoStream(strPDFMessage);
            strPDFMessage= "ET/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            //Get the End of the stream
            streamEnd=mPDF.Length;
            //Get the Length of the stream
            streamLen=streamEnd-streamStart;
            strPDFMessage= "endstream/nendobj/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
                    
            //Add 2 object to xRef
            xRefs.Add(mPDF.Length);
            strPDFMessage="2 0 obj/n"+ streamLen + "/nendobj/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
                        
            //Add Page to xRefs
            xRefs.Add(mPDF.Length);
            strPDFMessage="3 0 obj/n<</Type/Page/Parent 4 0 R/Contents 1 0 R>>/nendobj/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            
            //Build the Pages
            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);
            
            //Add font to xRefs
            xRefs.Add(mPDF.Length);
            strPDFMessage="5 0 obj/n<</Type/Font/Subtype/Type1/BaseFont/Courier/Encoding/WinAnsiEncoding>>/nendobj/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
                    
            //Add the catalog to xRefs
            xRefs.Add(mPDF.Length);
            strPDFMessage="6 0 obj/n<</Type/Catalog/Pages 4 0 R>>/nendobj/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
                        
            //xRefs Entry
            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);
            //Trailer for the PDF
            strPDFMessage="trailer/n<</n/Size "+ (xRefs.Count+1)+"/n/Root 6 0 R/n>>/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            //xRef location entry
            strPDFMessage="startxref/n" + streamStart+"/n%%EOF/n";
            ConvertToByteAndAddtoStream(strPDFMessage);
            //Write the PDF from Memory Stream to File Stream
            mPDF.WriteTo(pPDF.BaseStream);
            //Close the Stream
            mPDF.Close();
            pPDF.Close();
        }
    }
}