Barcode UPC-A

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

namespace UPCA
{
  class cUPCA
  {
    private Bitmap newBitmap;
    private Graphics g;
    private int barCodeHeight = 80;
    private int placeMarker = 0;
    private int imageWidth = 0;
    private float imageScale = 1;
    private string UPCABegin = "0000000000000101";
    private string[] UPCALeft = { "0001101", "0011001", "0010011", "0111101", "0100011", "0110001", "0101111", "0111011", "0110111", "0001011" };
    private string UPCAMiddle = "01010";
    private string[] UPCARight = { "1110010", "1100110", "1101100", "1000010", "1011100", "1001110", "1010000", "1000100", "1001000", "1110100" };
    private string UPCAEnd = "1010000000000000";

    public Image CreateBarCode(string txt, int scale)
    {
      Image img = null;
      imageWidth = 120;
      imageScale = scale;
      imageWidth = System.Convert.ToInt32(imageWidth * imageScale);
      int imageHeightHolder = System.Convert.ToInt32(barCodeHeight * imageScale);
      string incomingString = txt.ToUpper();
      if(incomingString.Length == 0)
      {
        return img;
      }
      int numberOfChars = incomingString.Length;
      newBitmap = new Bitmap((imageWidth), imageHeightHolder, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
      g = Graphics.FromImage(newBitmap);
      g.ScaleTransform(imageScale, imageScale);
      Rectangle newRec = new Rectangle(0, 0, (imageWidth), imageHeightHolder);
      g.FillRectangle(new SolidBrush(Color.White), newRec);
      placeMarker = 0;
      txt = txt.Substring(0, 11) + GetCheckSum(txt).ToString();
      int wholeSet = 0;
      for(wholeSet = 1; wholeSet <= System.Convert.ToInt32(incomingString.Length); wholeSet++)
      {
        int currentASCII = (int)Convert.ToChar((incomingString.Substring(wholeSet - 1, 1))) - 48;
        string currentLetter = "";
        if(wholeSet == 1)
        {
          DrawSet(UPCABegin, placeMarker, 0);
          DrawSet(UPCALeft[currentASCII], placeMarker, 0);
        }
        else if(wholeSet <= 5)
        {
          DrawSet(UPCALeft[currentASCII], placeMarker, 6);
        }
        else if(wholeSet == 6)
        {
          DrawSet(UPCALeft[currentASCII], placeMarker, 6);
          DrawSet(UPCAMiddle, placeMarker, 0);
        }
        else if(wholeSet <= 11)
        {
          DrawSet(UPCARight[currentASCII], placeMarker, 6);
        }
        else if(wholeSet == 12)
        {
          DrawSet(UPCARight[currentASCII], placeMarker, 0);
          DrawSet(UPCAEnd, placeMarker, 0);
        }
      }
      
      System.Drawing.Font font = new System.Drawing.Font("Courier New, Bold", 9);
      try
      {
        g.DrawString(txt.Substring(0, 1), font, Brushes.Black, new System.Drawing.PointF(0, 67));
        g.DrawString(txt.Substring(1, 5), font, Brushes.Black, new System.Drawing.PointF(22, 67));
        g.DrawString(txt.Substring(6, 5), font, Brushes.Black, new System.Drawing.PointF(60, 67));
        g.DrawString(txt.Substring(11, 1), font, Brushes.Black, new System.Drawing.PointF(108, 67));
      }
      finally
      {
        font.Dispose();
      }
      img = Image.FromHbitmap(newBitmap.GetHbitmap());
      return img;
    }

    public int GetCheckSum(string barCode)
    {
      string leftSideOfBarCode = barCode.Substring(0, 11);
      int total = 0;
      int currentDigit = 0;
      int i = 0;
      for( i = 0; i <= leftSideOfBarCode.Length - 1; i++)
      {
        currentDigit = Convert.ToInt32(leftSideOfBarCode.Substring(i, 1));
        if(((i - 1) % 2 == 0))
        {
          total += currentDigit * 1;
        }
        else
        {
          total += currentDigit * 3;
        }
      }
      int iCheckSum = (10 - (total % 10)) % 10;
      return iCheckSum;
    }

    private void DrawSet(string upcCode, int drawLocation, int barHeight)
    {
      int[] currentLetterArray = new int[upcCode.Length];
      placeMarker += upcCode.Length;
      barHeight = barCodeHeight - barHeight;
      int i = 0;
      for(i = 0; i <= upcCode.Length - 1; i++)
      {
        currentLetterArray[i] = Convert.ToInt16(upcCode.Substring(i, 1));
      }
      for(i = 0; i <= upcCode.Length - 1; i++)
      {
        if(currentLetterArray[i] == 0)
        {
          g.DrawLine(Pens.White, i + (drawLocation), 0, i + (drawLocation), barHeight - 6);
        }
        else if(currentLetterArray[i] == 1)
        {
          g.DrawLine(Pens.Black, i + (drawLocation), 0, i + (drawLocation), barHeight - 6);
        }
      }
    }

  }
}