The TALtech Bar Code ActiveX Control provides two means for generating bar codes in web pages. The first and easiest approach is to place a reference to the TALtech Bar Code ActiveX control in your HTML code for the web page and then use simple VBScript or JavaScript code in the HTML document to set the properties of the Bar Code control. This approach is a "Client Side Approach" where the bar codes are actually generated by the ActiveX control in the web client's PC. In this case, the Bar Code control is downloaded automatically from the web server to the client's PC and installed as an ActiveX component locally. Metatags in the HTML document provide information and a URL that instructs the client's browser to download and install the ActiveX control from the web server if the control is not already installed in the user's PC.

The down side to this approach is that ActiveX controls are only supported by Internet Explorer running under 32 bit Windows. Mac and UNIX users as well as Netscape users running Windows will not be able to display the bar codes in web pages that use this technique.

The up side to this approach is that the bar codes are rendered using Windows vector graphic GDI calls by the ActiveX control. This means that the bar codes that are produced will be extremely high quality and should print perfectly on any printer. If you want the highest quality bar codes that you can get and you have control over the type of browser and operating system that your web clients are running (for example on an intranet site), the client side technique is the better approach.

The fact that Mac, Unix and Netscape users are not able to produce bar codes using the client side approach obviously causes problems if you are developing a general web site where you have no control over the operating system or the browser that your web clients may be running.

For this situation, the only solution is to generate the bar codes on the web server as graphic images in either the GIF, PNG or JPEG file formats using either CGI/Perl scripting or Active Server Pages (ASP). All web browsers support the GIF and JPEG file formats and all versions of Netscape 4.0 (and above) or Internet Explorer 4.0 (and above) support the PNG file format.

The "server side" technique requires that the TALtech Bar Code ActiveX control (Plus version) be installed on the web server. You then write code (CGI/Perl or ASP) that calls the ActiveX control to produce GIF, PNG or JPEG images of your bar codes that are saved to temporary files on the server. The CGI/Perl or ASP code would also dynamically produce HTML documents containing Image tags that reference the bar code graphic files and feed the HTML documents back to the user's browser.

The advantage to this technique is that all web clients including Mac, UNIX and Netscape users will be able to display and print the resulting bar codes. Also, the client's browser does not need to download or install the ActiveX control locally thereby saving time for the web client.

The disadvantages to this technique are that the web server must be a Windows based server because ActiveX controls will only run under 32 bit Windows. You may need to check with your Internet Service Provider to make sure that they are running Windows based servers and also that they will allow you to install ActiveX controls on their servers.

Another disadvantage of the server side approach is that you must write code (CGI/Perl or ASP) in order to implement this technique. To make this as painless as possible, the TALtech Bar Code ActiveX Control Plus version comes complete with several CGI/Perl and ASP example programs that demonstrate how to implement server side bar code generation. The only other disadvantage to creating the bar codes on the server is that the bar codes are produced as raster style images (GIF, PNG or JPEG) which can reduce the image quality of the bar codes depending on how you create the bar codes in the first place and also depending on the type of printer that your web clients use to print the bar codes. If you follow a few simple guidelines when you create your bar codes on the server, the image quality issue can be eliminated and you should obtain extremely high quality bar codes that print and read perfectly.

Related Links

Creating Bar Codes on Web Pages - Client Side Overview.
Creating Bar Codes on Web Pages - Server Side Overview.
Creating Bar Codes on a Web Server Using Server Side Scripting - Technical Details
How to produce high quality raster style bar code images.
Generating Compressed or Uncompressed GIF Files With the TAL Bar Code ActiveX Control.