BarCode WbeService...

BarCode WbeService

The Article is come form codeproject website

Web address - http://www.codeproject.com/KB/cpp/wsbarcode.aspx

Introduction

Some days ago,I was asked to find a solution to create a barcode to be printed on documents produced by a web application. After trying to find some components that produced barcodes,I soon realized that their price was very high when dealing with an unlimited number of clients licences. I needed an alphanumeric barcode representation and the preferred barcode representation was Code39.

In order to expose this service to the maximum of clients while delivering a standardized solution,I thought of writing a web service that would generate the barcode dynamically and return it streamlined as an image.

This article describes the solution that I’ve implemented.

The Barcode Generation

Instead of writing a code39 barcode generator that mimics the algorithm for that barcode representation, my idea was to use one of the freely available barcode fonts to produce the barcode (http://www.squaregear.net/fonts/free3of9.shtml).

So my approach was simple:

1. Load the Barcode Font

2. Create an image object

3. Draw a string into that image using a code39 barcode font

4. Return that image serialized.

Using the Code39 Font...

The way to use a font in windows is simple, all you have to do is install it (by copying it to the c:\WINDOWS\Fonts - under XP) and just use it.

Unfortunately, the ASP.NET graphic context does not allow you to use any font (free3of9.ttf for example) because .NET GDI only uses/enumerates OpenType fonts. So what you have to do is create a temporary font object.

This method is very straighforward, as you can see in the code sample below:

// Create a private font collection

objectPrivateFontCollection pfc=new PrivateFontCollection();

// Load in the temporary barcode font

pfc.AddFontFile("c:\\barcodefont\\free3of9.ttf");

// Select the font family to use

FontFamily family=new FontFamily("Free 3 of 9",pfc);

// Create the font object with size 30

Font c39Font=new Font(family,30);

With this easy way, you get a font object mapped to the barcode font so that you can create the barcode.

Creating the Barcode Image Container

The image creation is very simple. .NET classes allow you to generate images on the fly. So, in order to create a image large enough to accommodate the barcode, first you need to determine the size that will be occupied by the code string drawing, using the barcode font.

You can do it using the MeasureString method:

// Create a temporary bitmap...

Bitmap tmpBitmap = new Bitmap(1,1,PixelFormat.Format32bppArgb);

objGraphics = Graphics.FromImage(tmpBitmap);

// measure the barcode size...

SizeF barCodeSize=objGraphics.MeasureString(barCodeString,c39Font);

The returned type barCodeSize has the width, and the height that will be occupied by the code string drawing.

Draw the Barcode

So now we need to draw the barcode. We will use the code39 barcode font object instantiated earlier.

Assuming the the barcode variable holds the barcode string, the required code is:

// Draw the barcode

objGraphics.DrawString(barCode, Code39Font, new solidBrush(Color.Black),0,0);

Please note that usualy the code39 barcodes are represented concatenating the char (*) at the beginning and end of the barcode string…meaning that code 123456 has to be written as *123456*. But I will leave that to your experience.

Serialize/Deserialize the Image

In order to return the image from the web service method, you now have to serialize the image, meaning that your web method has to return an array of bytes.

This way, you have to create a stream from the bitmap image, and return it as an array of bytes. Once again, the .NET framework makes it easy for us do perform that task:

// Create stream....

MemoryStream ms = new MemoryStream();

// save the image to the stream

objBitmap.Save(ms ,ImageFormat.Png);

//return an array of bytes....

return ms.GetBuffer();

On the other end (the client side) when you are consuming the web service, you need to be able to deserialize the array of bytes back to the image:

Byte[] imgBarcode;

// Call the webservice to create the barcode...

// Create a stream....

MemoryStream memStream = new MemoryStream(imgBarcode);

// Recreate the image from the stream Bitmap bmp=new Bitmap(memStream);

A final note about the sample code attached…

After creating the barcode web app that will be your webservice, you need to configure the web.config file in order to specify where your barcode font is located. Search for the following section and make your changes accordingly.

<appSettings>

<add key="BarCodeFontFile" value="c:\temp\font\FREE3OF9.TTF" />

<add key="BarCodeFontFamily" value="Free 3 of 9" />

</appSettings>

--the below is I changed the program to vb.net code.

-web service class: BarCode39.vb

Imports Microsoft.VisualBasic

Imports System

Imports System.Drawing

Imports System.Drawing.Imaging

Imports System.Drawing.Text

Imports System.IO

Imports System.Text.RegularExpressions

Namespace Barcodes

Public Class BarCode39

Private Const lint_ItemSepHeight = 3

Private lint_TitleSize As SizeF = SizeF.Empty

Private lint_BarCodeSize As SizeF = SizeF.Empty

Private lint_CodeStringSize As SizeF = SizeF.Empty

Private lstg_TitleString As String

Private lfnt_TitleFont As Font

Sub New()

lfnt_TitleFont = New Font("Arial", 10)

lfnt_CodeStringFont = New Font("Arial", 10)

End Sub

Public Property Title() As String

Get

Return lstg_TitleString

End Get

Set(ByVal value As String)

lstg_TitleString = value

End Set

End Property

Public Property TitleFont() As Font

Get

Return lfnt_TitleFont

End Get

Set(ByVal value As Font)

lfnt_TitleFont = value

End Set

End Property

Private lbool_ShowCodeString As Boolean

Private lfnt_CodeStringFont As Font

Public Property ShowCodeString() As Boolean

Get

Return lbool_ShowCodeString

End Get

Set(ByVal value As Boolean)

lbool_ShowCodeString = value

End Set

End Property

Public Property CodeStringFont() As Font

Get

Return lfnt_CodeStringFont

End Get

Set(ByVal value As Font)

lfnt_CodeStringFont = value

End Set

End Property

Private lfnt_C39Font As Font

Private lint_C39FontSize As Decimal = 12

Private lstg_C39FontFileName As String

Private lstg_C39FontFamilyName As String

Public Property FontFileName() As String

Get

Return lstg_C39FontFileName

End Get

Set(ByVal value As String)

lstg_C39FontFileName = value

End Set

End Property

Public Property FontFamilyName()

Get

Return lstg_C39FontFamilyName

End Get

Set(ByVal value)

lstg_C39FontFamilyName = value

End Set

End Property

Public Property FontSize() As Decimal

Get

Return lint_C39FontSize

End Get

Set(ByVal value As Decimal)

lint_C39FontSize = value

End Set

End Property

Private ReadOnly Property Code39Font() As Font

Get

If lfnt_C39Font Is Nothing Then

Dim pfc As PrivateFontCollection = New PrivateFontCollection

pfc.AddFontFile(lstg_C39FontFileName)

Dim family As FontFamily = New FontFamily(lstg_C39FontFamilyName, pfc)

lfnt_C39Font = New Font(family, lint_C39FontSize)

End If

Return lfnt_C39Font

End Get

End Property

Public Function GenerateBarcode(ByVal barcode As String) As Bitmap

Dim bcodeWidth As Integer = 0

Dim bcodeHeight As Integer = 0

Dim bcodeBitmap As Bitmap = CreateImageContainer(barcode, bcodeWidth, bcodeHeight)

Dim objGraphics As Graphics = Graphics.FromImage(bcodeBitmap)

objGraphics.FillRectangle(New SolidBrush(Color.White), New Rectangle(0, 0, bcodeWidth, bcodeHeight))

Dim vpos As Integer = 0

If lstg_TitleString <> "" Then

objGraphics.DrawString(lstg_TitleString, lfnt_TitleFont, New SolidBrush(Color.Black), XCentered((CInt(lint_TitleSize.Width)), bcodeWidth), vpos)

vpos += ((CInt(lint_TitleSize.Height)) + lint_ItemSepHeight)

End If

objGraphics.DrawString(barcode, Code39Font, New SolidBrush(Color.Black), XCentered(CInt(lint_BarCodeSize.Width), bcodeWidth), vpos)

If lbool_ShowCodeString Then

vpos += ((CInt(lint_BarCodeSize.Height)))

objGraphics.DrawString(barcode, lfnt_CodeStringFont, New SolidBrush(Color.Black), XCentered(CInt(lint_CodeStringSize.Width), bcodeWidth), vpos)

End If

Return bcodeBitmap

End Function

Private Function CreateImageContainer(ByVal barcode As String, ByRef bcodeWidth As Integer, ByRef bcodeHeight As Integer)

Dim objGraphics As Graphics

Dim tmpBitmap As Bitmap = New Bitmap(1, 1, PixelFormat.Format32bppArgb)

objGraphics = Graphics.FromImage(tmpBitmap)

If lstg_TitleString <> "" Then

lint_TitleSize = objGraphics.MeasureString(lstg_TitleString, lfnt_TitleFont)

bcodeWidth = CInt(lint_TitleSize.Width)

bcodeHeight = CInt(lint_TitleSize.Height + lint_ItemSepHeight)

End If

lint_BarCodeSize = objGraphics.MeasureString(barcode, Code39Font)

bcodeWidth = Max(bcodeWidth, CInt(lint_BarCodeSize.Width))

bcodeHeight += CInt(lint_BarCodeSize.Height)

If lbool_ShowCodeString Then

lint_CodeStringSize = objGraphics.MeasureString(barcode, lfnt_CodeStringFont)

bcodeWidth = Max(bcodeWidth, CInt(lint_CodeStringSize.Width))

bcodeHeight += lint_ItemSepHeight + CInt(lint_CodeStringSize.Height)

End If

objGraphics.Dispose()

tmpBitmap.Dispose()

Return (New Bitmap(bcodeWidth, bcodeHeight, PixelFormat.Format32bppArgb))

End Function

Private Function Max(ByVal v1 As Integer, ByVal v2 As String)

If v1 > v2 Then

Return v1

Else

Return v2

End If

End Function

Private Function XCentered(ByVal localWidth As Integer, ByVal globalWidht As Integer) As Integer

Return ((globalWidht - localWidth) / 2)

End Function

End Class

End Namespace

-Barcode Service: BarCodeService.asmx

Imports System.Web

Imports System.Web.Services

Imports System.Web.Services.Protocols

Imports System

Imports System.Collections

Imports System.ComponentModel

Imports System.Data

Imports System.Diagnostics

Imports System.Drawing

Imports System.Drawing.Imaging

Imports System.IO

Imports System.Configuration

<WebService(Namespace:="http://tempuri.org/")> _

<WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _

<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _

Public Class BarCodeService

Inherits System.Web.Services.WebService

<WebMethod()> _

Public Function HelloWorld() As String

Return "Hello World"

End Function

<WebMethod()> _

Public Function Code39(ByVal code As String, ByVal barSize As Integer, ByVal showCodeString As Boolean, ByVal title As String) As Byte()

Dim c39 As Barcodes.BarCode39 = New Barcodes.BarCode39

'Create stream....

Dim ms As MemoryStream = New MemoryStream()

c39.FontFamilyName = ConfigurationSettings.AppSettings.Get("BarCodeFontFamily")

c39.FontFileName = ConfigurationSettings.AppSettings.Get("BarCodeFontFile")

c39.FontSize = barSize

c39.ShowCodeString = showCodeString

If title + "" <> "" Then

c39.Title = title

End If

Dim objBitmap As Bitmap = c39.GenerateBarcode(code)

objBitmap.Save(ms, ImageFormat.Png)

'return bytes....

Return ms.GetBuffer()

End Function

End Class

-Web Client Call Web Service Generate Barcode

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim barCodeGen As New BarCodeLive.BarCodeService

barCodeGen.Credentials = System.Net.CredentialCache.DefaultCredentials

Dim barsize As Integer

barsize = System.Convert.ToInt32(Me.TextBox_BarCodeFontSize.Text)

Dim imgBarcode As System.Byte() = barCodeGen.Code39(Me.TextBox_BarCodeString.Text, barsize, Me.CheckBox_TitleShow.Checked, Nothing)

Dim memStream As MemoryStream = New MemoryStream(imgBarcode)

Dim xx As New System.Drawing.Bitmap(memStream)

' xx.SetPixel(10, 20, System.Drawing.Color.Empty)

margin: 0cm 0cm 0pt; text-align: le