Questions about adding barcode scanning capability
in [Visual Basic]
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From: Paulo on 14 May 2010 10:10 Hi, friends I want to add barcode scanning capability to a next release of my application. A barcode with the identification of the customer will be printed in a form. After to fill in the form, customer sends back the report to my client. The operator of my application should be able to read the customer identification with a barcode scanner and, at this time, should be automaticaly loaded a dialog in order the operator to update data. Searching in the internet I found inWikipedia some useful code to draw the barcode, but couldn't find any good tutorial: http://www.google.com/search?hl=en&lr=&q=vb+vb6+barcode+scan+draw+tutorial+source+-net+-dot&btnG=Search&aq=f&aqi=&aql=&oq=&gs_rfai= I am completely new to this, and have some questions: a) Is it possible to implement this? b) Which type of barcode should be used in this type of application? c) Which type of barcode scanner to buy for tests? d) How to detect if a barcode scanner device is attached to the client computer? e) How to get a barcode value in a variable in my application? Thanks for any advice, Paulo ----- _I want my Classic VB_
From: Saga on 14 May 2010 11:42 Inline. Saga "Paulo" <nospam.pmpcosta(a)netcabo.pt> wrote in message news:uF6%23e828KHA.2248(a)TK2MSFTNGP05.phx.gbl... > Hi, friends > > I want to add barcode scanning capability to a next release of my > application. A barcode with the identification of the customer will be > printed in a form. Is your app printing the form? After to fill in the form, customer sends back the report > to my client. The operator of my application should be able to read the > customer identification with a barcode scanner and, at this time, should > be automaticaly loaded a dialog in order the operator to update data. > So does that mean that your app only needs to read the barcode? > Searching in the internet I found inWikipedia some useful code to draw the > barcode, but couldn't find any good tutorial: > So does that mean that you also need to generate the barcode? If so, go back to Google and search for barcode fonts.This is the least painful way to draw the barcode when printing the form. > http://www.google.com/search?hl=en&lr=&q=vb+vb6+barcode+scan+draw+tutorial+source+-net+-dot&btnG=Search&aq=f&aqi=&aql=&oq=&gs_rfai= > > I am completely new to this, and have some questions: > > a) Is it possible to implement this? I am not sure if you only want to read the barcode (BC) or also generate it on the printed form. Either way, the answer is Yes, it is possible. > b) Which type of barcode should be used in this type of application? Depends on the customer id. Is it just digits? Does it include letters? Is it very long (8 chars or more)? Basically, the two types of barcodes that are used are Code 3 of 9 or Code 128. Go here to learn more about barcodes: http://www.barcodeisland.com/symbolgy.phtml > c) Which type of barcode scanner to buy for tests? Buy the brand and model that will be used in production. Symbol is a popular brand, but not the oinly one. Obviously, make sure that itis compatible with the barcode that you select, although many scanners are able to read different symbologies. > d) How to detect if a barcode scanner device is attached to the client > computer? This might not be possible, depending on the scanner type that you select. Fact is, the use of the scanner is supposed to be transparent to the application. Why would you want to check if a scanner is attached to the PC? If it is, just use it, if not, have the user type in the customer id. > e) How to get a barcode value in a variable in my application? > This depends on the type of BC scanner that you get. If it connects via the serial port then you might need a special routine that getsthe scanned data. In this case the ode will allow you to read in data from the serial port and assign it to any variable, data structre or text control that your applicaction has. If the scanner connects to the keyboard port then whatever you scan is piped through the keyboard interface as though you have typed it in yourself. In this case, the scanned data will end up anywhere where the text cursor is at. If you open Notepad, you can scan right into. Although the KB scanner requires less code (in fact none at all) some like the serial scanner because they offer more ocntrol, at the cost of needing more code. If the scanner connects to the USB port then it might have the ability to mimic either of the the modes described above. Some don;t like the KB scanner becasue this allows the user to positon the text cursosr anywhere where text input is allowed and be able to read BCs into the text area. This might cause the user to inout the scanned data into text areas where this is not desired. It cal also be a breach of security because it is very easy to collect scanned data into any application that accepts text input, such as text editor, word processors and many more. Inthe end, the needs dictate the type of scanner and barcode that you will be using. If you use the scanner that connects to the KB, have your app only allow input into the specific field where the cust id goes. Only after this field has been entered/scanned will the other fields be available. While this is not a fool proof method, it does minimize data enry errors. > Thanks for any advice, > > Paulo > ----- > _I want my Classic VB_ > >
From: David Kerber on 14 May 2010 13:18 In article <uF6#e828KHA.2248(a)TK2MSFTNGP05.phx.gbl>, nospam.pmpcosta(a)netcabo.pt says... > > Hi, friends > > I want to add barcode scanning capability to a next release of my > application. A barcode with the identification of the customer will be I just did this in the last 6 weeks for my app. .... I didn't read your link, but: > a) Is it possible to implement this? Adding barcode printing and scanning is easy. > b) Which type of barcode should be used in this type of application? Code 39 (officially "3 of 9") is probably the most common. The standard code 39 does numbers and capital letters, and maybe a couple of punctuation chars (I don't remember for sure which ones becasue we don't use them). Code 39 Extended adds lower-case letters and most of the rest of the basic printable ASCII character set. > c) Which type of barcode scanner to buy for tests? Any. We use one by a company called Wasp: www.waspbarcode.com. Their starter set is pretty inexpensive ($139 IIRC) for a scanner and two or three basic software applications. > d) How to detect if a barcode scanner device is attached to the client > computer? You don't really need to: the scanner acts like a keyboard, so you put the focus into a text entry box, and your users can either type into it, or use the scanner, whichever they feel like. > e) How to get a barcode value in a variable in my application? See question d; It comes in as a string of characters. > > Thanks for any advice, There are lots of free barcode fonts out there, and the two I've tried both work fine, so you have a lot of options when it comes to generating your stickers. D
From: Helmut Meukel on 14 May 2010 14:19 The simplest way to attach a barcode scanner is to use one which is connected between keyboard and PC, thus being transparent for OS and your app. Most scanners are able to decode different barcodes types and transfer the date to the PC. Use for your tests the same type of scanner that will be used in production! For printing the barcodes, try different free Truetype fonts. I found it's best to use the same printer type and paper as will be used in production and try out different font sizes. I installed the Truetype fonts on my PC and used Word to print the different fonts in different sizes. Then I used a tiny test program to read the barcode into a textbox. Some fonts made problems in some font sizes. In our case we had to use colored paper - light green - and a HP Laserjet and the scanner had problems to read the barcodes from this paper with font sizes below 14. With one font the scanner had no problem with size 12 and 15 but choked with font sizes 13 and 14. We used Code39, because our OrderNo contained only numbers and uppercase characters. Helmut. "Paulo" <nospam.pmpcosta(a)netcabo.pt> schrieb im Newsbeitrag news:uF6%23e828KHA.2248(a)TK2MSFTNGP05.phx.gbl... > Hi, friends > > I want to add barcode scanning capability to a next release of my application. > A barcode with the identification of the customer will be printed in a form. > After to fill in the form, customer sends back the report to my client. The > operator of my application should be able to read the customer identification > with a barcode scanner and, at this time, should be automaticaly loaded a > dialog in order the operator to update data. > > I am completely new to this, and have some questions: > > a) Is it possible to implement this? > b) Which type of barcode should be used in this type of application? > c) Which type of barcode scanner to buy for tests? > d) How to detect if a barcode scanner device is attached to the client > computer? > e) How to get a barcode value in a variable in my application? > > Thanks for any advice, > > Paulo > -----
From: Paulo on 14 May 2010 14:36
Hi, Saga "Saga" <antiSpam(a)nowhere.com> wrote: > Is your app printing the form? > ... ... > So does that mean that you also need to generate the barcode? If so, go > back > to Google and search for barcode fonts.This is the least painful way to > draw > the barcode when printing the form. Yes, it is to be printed. I think this part is done, because I found some code and fonts at SourceForge: http://sourceforge.net/projects/openbarcodes/files/openbarcodes/openbarcodes.zip > Depends on the customer id. Is it just digits? Does it include letters? > Is it very long (8 chars or more)? Basically, the two types of barcodes > that are used are Code 3 of 9 or Code 128. The customes Id is numeric only (a Long data type) so it will be only a few digits. > Go here to learn more about barcodes: > http://www.barcodeisland.com/symbolgy.phtml Very good stuff. Actually, I will not need to know if a barcode scanner is attached or not. I'm learning... Thanks a lot for your advice, Saga. Paulo ----- _I want my Classic VB_ |