asp.net(c#)生成EAN13条形码,webform版本

        做一个项目需要用到条形码，在网上搜索一下，基本上都是winform版本。于是我就找了一个老外的代码修改了一下，版权属于原作者。
          写一个条形码的类，名称为EAN13BarCode.cs，代码如下：

using  System;
using  System.Text;
using  System.Drawing;
using  System.Web;

namespace  Utility
... {
    /**//// <summary>
    /// EAN13BarCode 的摘要说明。
    /// </summary>
    public class EAN13BarCode
    ...{
        private string _sName = "EAN13";

        private float _fMinimumAllowableScale = .8f;
        private float _fMaximumAllowableScale = 2.0f;

        // This is the nomimal size recommended by the EAN.
        private float _fWidth = 37.29f;
        private float _fHeight = 25.93f;
        private float _fFontSize = 8.0f;
        private float _fScale = 1.0f;

        // Left Hand Digits.
        private string [] _aOddLeft = ...{ "0001101", "0011001", "0010011", "0111101", 
                                          "0100011", "0110001", "0101111", "0111011", 
                                          "0110111", "0001011" };

        private string [] _aEvenLeft = ...{ "0100111", "0110011", "0011011", "0100001", 
                                           "0011101", "0111001", "0000101", "0010001", 
                                           "0001001", "0010111" };

        // Right Hand Digits.
        private string [] _aRight = ...{ "1110010", "1100110", "1101100", "1000010", 
                                        "1011100", "1001110", "1010000", "1000100", 
                                        "1001000", "1110100" };

        private string _sQuiteZone = "000000000";

        private string _sLeadTail = "101";

        private string _sSeparator = "01010";

        private string _sCountryCode = "00";
        private string _sManufacturerCode;
        private string _sProductCode;
        private string _sChecksumDigit;

        public EAN13BarCode( )
        ...{

        }

        public EAN13BarCode( string mfgNumber, string productId )
        ...{
            this.CountryCode = "00";
            this.ManufacturerCode = mfgNumber;
            this.ProductCode = productId;
            this.CalculateChecksumDigit( );
        }

        public EAN13BarCode( string countryCode, string mfgNumber, string productId )
        ...{
            this.CountryCode = countryCode;
            this.ManufacturerCode = mfgNumber;
            this.ProductCode = productId;
            this.CalculateChecksumDigit( );
        }

        public EAN13BarCode( string countryCode, string mfgNumber, string productId, string checkDigit )
        ...{
            this.CountryCode = countryCode;
            this.ManufacturerCode = mfgNumber;
            this.ProductCode = productId;
            this.ChecksumDigit = checkDigit;
        }

        public static string getENA13Code(string Numbers12bit)
        ...{
            int c1 = 0;
            int c2 = 0;

            for (int i=0; i<11;  i= i+2)
            ...{
                c1 += int.Parse(Numbers12bit[i].ToString());
                c2 += int.Parse(Numbers12bit[i+1].ToString());
            }

            int c3 = c1 + c2 *3;

            c3 = c3  - c3/10 *10;

            if (c3 == 0)
            ...{
                return Numbers12bit + 0;
            }
            else
            ...{
                int N = 10 - c3;

                return Numbers12bit + N.ToString();
            }
        }
        public void DrawEan13Barcode(System.Drawing.Graphics g, System.Drawing.Point pt)
        ...{
            float width = this.Width * this.Scale;
            float height = this.Height * this.Scale;

            //    EAN13 Barcode should be a total of 113 modules wide.
            float lineWidth = width / 113f;

            g.Clear(Color.White);
            // Save the GraphicsState.
            System.Drawing.Drawing2D.GraphicsState gs = g.Save( );

            // Set the PageUnit to Inch because all of our measurements are in inches.
            g.PageUnit = System.Drawing.GraphicsUnit.Millimeter;

            // Set the PageScale to 1, so a millimeter will represent a true millimeter.
            g.PageScale = 1;

            System.Drawing.SolidBrush brush = new System.Drawing.SolidBrush( System.Drawing.Color.Black );

            float xPosition = 0;

            System.Text.StringBuilder strbEAN13 = new System.Text.StringBuilder( );
            System.Text.StringBuilder sbTemp = new System.Text.StringBuilder( );

            float xStart = pt.X;
            float yStart = pt.Y;
            float xEnd = 0;

            System.Drawing.Font font = new System.Drawing.Font( "Arial", this._fFontSize * this.Scale );

            // Calculate the Check Digit.
            this.CalculateChecksumDigit( );

            sbTemp.AppendFormat( "{0}{1}{2}{3}", 
                this.CountryCode,
                this.ManufacturerCode,
                this.ProductCode, 
                this.ChecksumDigit );


            string sTemp = sbTemp.ToString( );

            string sLeftPattern = "";