先写一个类

#region Using directives

using System;
using System.Text;

#endregion

namespace Ean13Barcode2005
{
 public class Ean13
 {
  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 Ean13( )
  {

  }

  public Ean13( string mfgNumber, string productId )
  {
   this.CountryCode = "00";
   this.ManufacturerCode = mfgNumber;
   this.ProductCode = productId;
   this.CalculateChecksumDigit( );
  }

  public Ean13( string countryCode, string mfgNumber, string productId )
  {
   this.CountryCode = countryCode;
   this.ManufacturerCode = mfgNumber;
   this.ProductCode = productId;
   this.CalculateChecksumDigit( );
  }

  public Ean13( string countryCode, string mfgNumber, string productId, string checkDigit )
  {
   this.CountryCode = countryCode;
   this.ManufacturerCode = mfgNumber;
   this.ProductCode = productId;
   this.ChecksumDigit = checkDigit;
  }

  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;

   // 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 = "";

   // Convert the left hand numbers.
   sLeftPattern = ConvertLeftPattern( sTemp.Substring( 0, 7 ) );

   // Build the UPC Code.
   strbEAN13.AppendFormat( "{0}{1}{2}{3}{4}{1}{0}",
    this._sQuiteZone, this._sLeadTail,
    sLeftPattern,     
    this._sSeparator,
    ConvertToDigitPatterns( sTemp.Substring( 7 ), this._aRight ) );

   string sTempUPC = strbEAN13.ToString( );

   float fTextHeight = g.MeasureString( sTempUPC, font ).Height;

   // Draw the barcode lines.
   for( int i = 0; i < strbEAN13.Length; i++ )
   {
    if( sTempUPC.Substring( i, 1 ) == "1" )
    {
     if( xStart == pt.X )
      xStart = xPosition;

     // Save room for the UPC number below the bar code.
     if( ( i > 12 && i < 55 ) || ( i > 57 && i < 101 ) )
      // Draw space for the number
      g.FillRectangle( brush, xPosition, yStart, lineWidth, height - fTextHeight );
     else
      // Draw a full line.
      g.FillRectangle( brush, xPosition, yStart, lineWidth, height );
    }

    xPosition += lineWidth;
    xEnd = xPosition;
   }

   // Draw the upc numbers below the line.
   xPosition = xStart - g.MeasureString( this.CountryCode.Substring( 0, 1 ), font ).Width;
   float yPosition = yStart + ( height - fTextHeight );

   // Draw 1st digit of the country code.
   g.DrawString( sTemp.Substring( 0, 1 ), font, brush, new System.Drawing.PointF( xPosition, yPosition ) );

   xPosition += ( g.MeasureString( sTemp.Substring( 0, 1 ), font ).Width + 43 * lineWidth ) -
    ( g.MeasureString( sTemp.Substring( 1, 6 ), font ).Width );

   // Draw MFG Number.
   g.DrawString( sTemp.Substring( 1, 6 ), font, brush, new System.Drawing.PointF( xPosition, yPosition ) );

   xPosition += g.MeasureString( sTemp.Substring( 1, 6 ), font ).Width + ( 11 * lineWidth );

   // Draw Product ID.
   g.DrawString( sTemp.Substring( 7 ), font, brush, new System.Drawing.PointF( xPosition, yPosition ) );

   // Restore the GraphicsState.
   g.Restore( gs );
  }

  public System.Drawing.Bitmap CreateBitmap( )
  {
   float tempWidth = ( this.Width * this.Scale ) * 100 ;
   float tempHeight = ( this.Height * this.Scale ) * 100;

   System.Drawing.Bitmap bmp = new System.Drawing.Bitmap( (int)tempWidth, (int)tempHeight );

   System.Drawing.Graphics g = System.Drawing.Graphics.FromImage( bmp );
   this.DrawEan13Barcode( g, new System.Drawing.Point( 0, 0 ) );
   g.Dispose( );
   return bmp;
  }

  private string ConvertLeftPattern( string sLeft )
  {
   switch( sLeft.Substring( 0, 1 ) )
   {
    case "0":
     return CountryCode0( sLeft.Substring( 1 ) );
     
    case "1":
     return CountryCode1( sLeft.Substring( 1 ) );

    case "2":
     return CountryCode2( sLeft.Substring( 1 ) );

    case "3":
     return CountryCode3( sLeft.Substring( 1 ) );

    case "4":
     return CountryCode4( sLeft.Substring( 1 ) );

    case "5":
     return CountryCode5( sLeft.Substring( 1 ) );

    case "6":
     return CountryCode6( sLeft.Substring( 1 ) );

    case "7":
     return CountryCode7( sLeft.Substring( 1 ) );

    case "8":
     return CountryCode8( sLeft.Substring( 1 ) );

    case "9":
     return CountryCode9( sLeft.Substring( 1 ) );

    default:
     return "";
   }
  }

  private string CountryCode0( string sLeft )
  {
   // 0 Odd Odd  Odd  Odd  Odd  Odd 
   return ConvertToDigitPatterns( sLeft, this._aOddLeft );
  }

  private string CountryCode1( string sLeft )
  {
   // 1 Odd Odd  Even Odd  Even Even 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   // The two lines below could be replaced with this:
   // sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 2 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aOddLeft ) );
   // The two lines below could be replaced with this:
   // sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 2 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aEvenLeft ) );
   return sReturn.ToString( );
  }

  
  private string CountryCode2( string sLeft )
  {
   // 2 Odd Odd  Even Even Odd  Even 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aEvenLeft ) );
   return sReturn.ToString( );
  }

  private string CountryCode3( string sLeft )
  {
   // 3 Odd Odd  Even Even Even Odd 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aOddLeft ) );
   return sReturn.ToString( );
  }

  private string CountryCode4( string sLeft )
  {
   // 4 Odd Even Odd  Odd  Even Even 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aEvenLeft ) );
   return sReturn.ToString( );
  }

  
  private string CountryCode5( string sLeft )
  {
   // 5 Odd Even Even Odd  Odd  Even 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aEvenLeft ) );
   return sReturn.ToString( );
  }
  

  private string CountryCode6( string sLeft )
  {
   // 6 Odd Even Even Even Odd  Odd 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aOddLeft ) );
   return sReturn.ToString( );
  }

  
  private string CountryCode7( string sLeft )
  {
   // 7 Odd Even Odd  Even Odd  Even
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aEvenLeft ) );
   return sReturn.ToString( );
  }

   
  private string CountryCode8( string sLeft )
  {
   // 8 Odd Even Odd  Even Even Odd 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aOddLeft ) );
   return sReturn.ToString( );
  }

  
  private string CountryCode9( string sLeft )
  {
   // 9 Odd Even Even Odd  Even Odd 
   System.Text.StringBuilder sReturn = new StringBuilder( );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 0, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 1, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 2, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 3, 1 ), this._aOddLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 4, 1 ), this._aEvenLeft ) );
   sReturn.Append( ConvertToDigitPatterns( sLeft.Substring( 5, 1 ), this._aOddLeft ) );
   return sReturn.ToString( );
  }

  private string ConvertToDigitPatterns( string inputNumber, string [] patterns )
  {
   System.Text.StringBuilder sbTemp = new StringBuilder( );
   int iIndex = 0;
   for( int i = 0; i < inputNumber.Length; i++ )
   {
    iIndex = Convert.ToInt32( inputNumber.Substring( i, 1 ) );
    sbTemp.Append( patterns[iIndex] );
   }
   return sbTemp.ToString( );
  }

  public void CalculateChecksumDigit( )
  {
   string sTemp = this.CountryCode + this.ManufacturerCode + this.ProductCode;
   int iSum = 0;
   int iDigit = 0;

   // Calculate the checksum digit here.
   for( int i = sTemp.Length; i >= 1; i-- )
   {
    iDigit = Convert.ToInt32( sTemp.Substring( i - 1, 1 ) );
    if( i % 2 == 0 )
    { // odd
     iSum += iDigit * 3;
    }
    else
    { // even
     iSum += iDigit * 1;
    }
   }

   int iCheckSum = ( 10 - ( iSum % 10 )  ) % 10;
   this.ChecksumDigit = iCheckSum.ToString( );

  }

  #region -- Attributes/Properties --

  public string Name
  {
   get
   {
    return _sName;
   }
  }

  public float MinimumAllowableScale
  {
   get
   {
    return _fMinimumAllowableScale;
   }
  }

  public float MaximumAllowableScale
  {
   get
   {
    return _fMaximumAllowableScale;
   }
  }

  public float Width
  {
   get
   {
    return _fWidth;
   }
  }

  public float Height
  {
   get
   {
    return _fHeight;
   }
  }

  public float FontSize
  {
   get
   {
    return _fFontSize;
   }
  }

  public float Scale
  {
   get
   {
    return _fScale;
   }

   set
   {
    if( value < this._fMinimumAllowableScale || value > this._fMaximumAllowableScale )
     throw new Exception( "Scale value out of allowable range.  Value must be between " + 
      this._fMinimumAllowableScale.ToString( ) + " and " + 
      this._fMaximumAllowableScale.ToString( ) );
    _fScale = value;
   }
  }

  public string CountryCode
  {
   get
   {
    return _sCountryCode;
   }

   set
   {
    while( value.Length < 2 )
    {
     value = "http://www.mamicode.com/0" + value;
    }
    _sCountryCode = value;
   }
  }

  public string ManufacturerCode
  {
   get
   {
    return _sManufacturerCode;
   }

   set
   {
    _sManufacturerCode = value;
   }
  }

  public string ProductCode
  {
   get
   {
    return _sProductCode;
   }

   set
   {
    _sProductCode = value;
   }
  }

  public string ChecksumDigit
  {
   get
   {
    return _sChecksumDigit;
   }

   set
   {
    int iValue = http://www.mamicode.com/Convert.ToInt32( value );
    if( iValue < 0 || iValue > 9 )
     throw new Exception( "The Check Digit mst be between 0 and 9." );
    _sChecksumDigit = value;
   }
  }

  #endregion -- Attributes/Properties --

 }
}

这是后台代码

using System;
using System.Drawing;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace Ean13Barcode2005
{
 /// <summary>
 /// Summary description for Form1.
 /// </summary>
 partial class frmEan13 : Form
 {
  private Ean13 ean13 = null;

  public frmEan13( )
  {
   InitializeComponent( );
   cboScale.SelectedIndex = 2;
  }

  private void CreateEan13( )
  {
   ean13 = new Ean13( );
   ean13.CountryCode = txtCountryCode.Text;
   ean13.ManufacturerCode = txtManufacturerCode.Text;
   ean13.ProductCode = txtProductCode.Text;
   if( txtChecksumDigit.Text.Length > 0 )
    ean13.ChecksumDigit = txtChecksumDigit.Text;
  }

  private void butDraw_Click(object sender, EventArgs e)
  {
   System.Drawing.Graphics g = this.picBarcode.CreateGraphics( );

   g.FillRectangle( new System.Drawing.SolidBrush( System.Drawing.SystemColors.Control ),
    new Rectangle( 0, 0, picBarcode.Width, picBarcode.Height ) );

   CreateEan13( );
   ean13.Scale = (float)Convert.ToDecimal( cboScale.Items [cboScale.SelectedIndex] );
   ean13.DrawEan13Barcode( g, new System.Drawing.Point( 0, 0 ) );
   txtChecksumDigit.Text = ean13.ChecksumDigit;
   g.Dispose( );
  }

  private void butPrint_Click(object sender, EventArgs e)
  {
   System.Drawing.Printing.PrintDocument pd = new System.Drawing.Printing.PrintDocument( );
   pd.PrintPage += new System.Drawing.Printing.PrintPageEventHandler( this.pd_PrintPage );
   pd.Print( );
  }

  private void pd_PrintPage( object sender, System.Drawing.Printing.PrintPageEventArgs ev )
  {
   CreateEan13( );
   ean13.Scale = ( float )Convert.ToDecimal( cboScale.Items [cboScale.SelectedIndex] );
   ean13.DrawEan13Barcode( ev.Graphics, new System.Drawing.Point( 0, 0 ) );
   txtChecksumDigit.Text = ean13.ChecksumDigit;

   // Add Code here to print other information.
   ev.Graphics.Dispose( );
  }

  private void butCreateBitmap_Click(object sender, EventArgs e)
  {
   CreateEan13( );
   ean13.Scale = ( float )Convert.ToDecimal( cboScale.Items [cboScale.SelectedIndex] );

   System.Drawing.Bitmap bmp = ean13.CreateBitmap( );
   this.picBarcode.Image = bmp;
  }

 }
}