Barcode with VB.NET

  • Thread starter Thread starter Mat
  • Start date Start date
Hi,

There are a number of ActiveX controls that can be used to generate/print
barcodes (and some Fonts that may be downloaded and used instead).
Examples: www.mabry.com, www.taltech.com, etc.

Here is my standard Barcode statement:

Reading barcodes requires hardware. There are at least three different ways
to interface purpose-build readers (ones that do not use cameras or
scanners). You can use a reader that uses a keyboard "wedge." This inserts
scanned data, just as though it had been typed at the keyboard. You set
focus to a textbox, and read the data in the KeyPress event. A similar
alternative is to use a USB scanner. These are installed as a keyboard, and
work the same way as the "wedge" type devices, but connect to the USB port,
instead of inline with the keyboard. My preference is to use barcode
readers that use a serial interface. You then can use MSComm (or
equivalent) to read the data, and there is no issue with maintaining focus
in a textbox -- thus this form of hardware seems, to me, to be more
"industrial strength." There are a variety of manufacturers of all of these
devices.

Dick
--
Richard Grier (Microsoft Visual Basic MVP)

See www.hardandsoftware.net for contact information.

Author of Visual Basic Programmer's Guide to Serial Communications, 3rd
Edition ISBN 1-890422-27-4 (391 pages) published February 2002.
 
check out http://www.renderbar.com/sample.php

they have an activex control but they also show the major 1D barcode
specifications, javascript source code, and examples of using both the
javascript to generate barcodes on web pages and integrating their control
in excel.

hth,

steve
 
The best tools for printing bar codes from a VB.NET application are
the TAL Bar Code DLLs. For more information, visit:
http://www.taltech.com/TALtech_web/products/dll_barcodes.html

You can also download a sample VB.NET program that demonstrates how to
use the TAL Bar Code DLLs in VB.NET from the follwowing URL:
http://www.taltech.com/TALtech_web/support/bcdlls/dllkbsc.htm

For reading bar codes into your applciation you have several options.

Most bar code readers are available with one of two output options.
The first option is called "Keyboard Wedge" output where you unplug
your keyboard, plug the bar code reader into the keyboard port on your
PC and then plug your keyboard into the bar code reader. This
arrangement makes the bar code reader appear as it it were simply a
second keyboard. Your original keyboard continues to work as normal
however when you read a bar code, the data encoded in the bar code
appears to any application running on your PC as if it were typed in.
The keyboard wedge interface is extremely simple however it has a few
drawbacks. If you swipe a bar code, the cursor has to be in the
correct input field in the correct application otherwise you end up
reading bar code data into whatever application has the focus. This
can cause all sorts of potential problems as you can imagine. The
keyboard output also is limited in that you cannot modify the data in
any way before sending it into the program that is to receive the
data. For example, if you needed to parse a bar code message up into
pieces or remove some of a bar code message or add in a date or time
stamp you would not be able to with a normal keyboard wedge reader.

The other possible output option is to get a bar code reader with an
RS232 or "Serial" interface. With these types of bar code readers, you
connect the reader to an available serial port on the back of your PC.
You would then need to either write code in your application to open
the serial port and read the data directly into your program or use a
program called a "Software Wedge" to take the data from the bar code
reader and feed it to your application. The disadvantage to this
approach is that it is a little more complex however you gain much
more control over how and where your data ends up when you read a bar
code. With custom serial I/O code or with a Software Wedge, you can
control exactly where the data goes in the target application and you
can also perform all sorts of modifications on the data before it is
sent to the application.

TAL Tehchnologies sells a product called WinWedge which is a Software
Wedge for Windows. Visit: http://www.taltech.com for more information.

This web site is also an extremely good place to obtain information
about bar coding in general.
 
if you don't want to pay the big bucks for tal barcode stuff, check out
http://www.renderbar.com. if you don't want to buy theirs, then read their
barcode specification pages and simply translate their free javascripted
versions into .net.

cool stuff if i do say so myself. ;^)

steve
 
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