Accurate browser detection

Oct 13, 2025 by talynt.org 79 views

Introduction

As a web developer, you may have encountered situations where you need to determine the type of browser a visitor is using on your website. This information can be useful for various purposes, such as serving different content based on the browser type or version. In this article, we will discuss how to use browscap.dll on a Windows Server running IIS and Classic ASP.

What is browscap.dll?

browscap.dll is a dynamic link library (DLL) that comes with the Internet Information Services (IIS) on Windows Server. It is used to determine the type of browser a visitor is using, based on the information provided by the browser itself. The DLL uses a configuration file called browscap.ini to map the browser information to a specific browser type.

Benefits of using browscap.dll

Using browscap.dll has several benefits, including:

No JavaScript required: Unlike fingerprinting methods that require JavaScript to be enabled, browscap.dll works without any client-side scripting.
Accurate browser detection: browscap.dll uses the information provided by the browser itself, making it a more accurate method of browser detection.
Easy to implement: Using browscap.dll is relatively easy, as it comes with IIS and can be configured using a simple configuration file.

Prerequisites

Before you can use browscap.dll, you need to have the following:

Windows Server: You need to be running a Windows Server operating system.
IIS: You need to have IIS installed on your Windows Server.
Classic ASP: You need to have Classic ASP installed on your IIS server.
browscap.dll: You need to have the browscap.dll file installed on your IIS server.

Configuring browscap.dll

To configure browscap.dll, you need to create a browscap.ini file and place it in the correct location. Here are the steps:

Create a browscap.ini file: Create a new text file called browscap.ini and add the following lines to it:

[version]
version=2.1
[browscap]
browser=*
platform=*
crawler=*
mobile=*

Place the browscap.ini file in the correct location: Place the browscap.ini file in the C:\Windows\System32\inetsrv directory.
Configure the browscap.dll file: Open the IIS Manager and navigate to the Application Pools section. Select the application pool that you want to use with browscap.dll and click on the Advanced Settings button. In the Advanced Settings window, click on the Configuration button and select the browscap.dll file from the list.

Using browscap.dll in Classic ASP

To use browscap.dll in Classic ASP, you need to create a new ASP page and add the following code to it:

<%
Dim browser
Dim platform
Dim crawler
Dim mobile
browser = Request.ServerVariables("HTTP_USER_AGENT")
platform = Request.ServerVariables("HTTP_USER_AGENT")
crawler = Request.ServerVariables("HTTP_USER_AGENT")
mobile = Request.ServerVariables("HTTP_USER_AGENT")
Set objBrowscap = Server.CreateObject("Browscap.Browscap")
objBrowscap.Init("C:\Windows\System32\inetsrv\browscap.ini")
Dim browserType
browserType = objBrowscap.GetBrowser(browser)
Response.Write "Browser Type: " & browserType & "<br>"
Response.Write "Platform: " & platform & "<br>"
Response.Write "Crawler: " & crawler & "<br>"
Response.Write "Mobile: " & mobile & "<br>"
%>

This code creates a new object called objBrowscap and initializes it with the browscap.ini file. It then uses the GetBrowser method to determine the browser type based on the HTTP_USER_AGENT header.

Conclusion

In this article, we discussed how to use browscap.dll on a Windows Server running IIS and Classic ASP. We covered the benefits of using browscap.dll, the prerequisites for using it, and the steps for configuring and using it in Classic ASP. By following the steps outlined in this article, you should be able to use browscap.dll to determine the type of browser a visitor is using on your website.

Troubleshooting

If you encounter any issues while using browscap.dll, here are some troubleshooting tips:

Check the browscap.ini file: Make sure that the browscap.ini file is correctly configured and placed in the correct location.
Check the browscap.dll file: Make sure that the browscap.dll file is correctly installed and configured.
Check the HTTP_USER_AGENT header: Make sure that the HTTP_USER_AGENT header is correctly set in the browser.
Check the Classic ASP code: Make sure that the Classic ASP code is correctly written and that the browscap.dll object is correctly initialized.

Additional Resources

For more information on using browscap.dll, you can refer to the following resources:

Microsoft documentation: The official Microsoft documentation for browscap.dll can be found on the Microsoft website.
Browscap documentation: The official Browscap documentation can be found on the Browscap website.
Classic ASP documentation: The official Classic ASP documentation can be found on the Microsoft website.

FAQs

Here are some frequently asked questions about using browscap.dll:

Q: What is the difference between browscap.dll and fingerprinting? A: browscap.dll uses the information provided by the browser itself, while fingerprinting uses client-side scripting to collect information about the browser.
Q: How do I configure browscap.dll? A: You need to create a browscap.ini file and place it in the correct location. You also need to configure the browscap.dll file in the IIS Manager.
Q: How do I use browscap.dll in Classic ASP? A: You need to create a new ASP page and add the code to it. You also need to initialize the browscap.dll object and use the GetBrowser method to determine the browser type.
Frequently Asked Questions (FAQs) about Using Browscap.dll ================================================================

Q: What is the difference between browscap.dll and fingerprinting?

A: browscap.dll uses the information provided by the browser itself, while fingerprinting uses client-side scripting to collect information about the browser. browscap.dll is a more accurate and reliable method of browser detection, as it uses the information provided by the browser itself, whereas fingerprinting can be blocked by users who disable JavaScript.

Q: How do I configure browscap.dll?

A: To configure browscap.dll, you need to create a browscap.ini file and place it in the correct location. You also need to configure the browscap.dll file in the IIS Manager. Here are the steps to configure browscap.dll:

Create a new text file called browscap.ini and add the following lines to it:

[version]
version=2.1
[browscap]
browser=*
platform=*
crawler=*
mobile=*

Place the browscap.ini file in the C:\Windows\System32\inetsrv directory.
Open the IIS Manager and navigate to the Application Pools section.
Select the application pool that you want to use with browscap.dll and click on the Advanced Settings button.
In the Advanced Settings window, click on the Configuration button and select the browscap.dll file from the list.

Q: How do I use browscap.dll in Classic ASP?

A: To use browscap.dll in Classic ASP, you need to create a new ASP page and add the following code to it:

<%
Dim browser
Dim platform
Dim crawler
Dim mobile
browser = Request.ServerVariables("HTTP_USER_AGENT")
platform = Request.ServerVariables("HTTP_USER_AGENT")
crawler = Request.ServerVariables("HTTP_USER_AGENT")
mobile = Request.ServerVariables("HTTP_USER_AGENT")
Set objBrowscap = Server.CreateObject("Browscap.Browscap")
objBrowscap.Init("C:\Windows\System32\inetsrv\browscap.ini")
Dim browserType
browserType = objBrowscap.GetBrowser(browser)
Response.Write "Browser Type: " & browserType & "<br>"
Response.Write "Platform: " & platform & "<br>"
Response.Write "Crawler: " & crawler & "<br>"
Response.Write "Mobile: " & mobile & "<br>"
%>

Q: What are the benefits of using browscap.dll?

A: The benefits of using browscap.dll include:

No JavaScript required: Unlike fingerprinting methods that require JavaScript to be enabled, browscap.dll works without any client-side scripting.
Accurate browser detection: browscap.dll uses the information provided by the browser itself, making it a more accurate method of browser detection.
Easy to implement: Using browscap.dll is relatively easy, as it comes with IIS and can be configured using a simple configuration file.

Q: What are the limitations of using browscap.dll?

A: The limitations of using browscap.dll include:

Limited browser support: browscap.dll may not support all browsers, especially newer ones.
Limited platform support: browscap.dll may not support all platforms, especially mobile devices.
Requires IIS: browscap.dll requires IIS to be installed and configured.

Q: Can I use browscap.dll with other web servers?

A: Yes, you can use browscap.dll with other web servers, but you need to configure it manually. Here are the steps to configure browscap.dll with other web servers:

Create a new text file called browscap.ini and add the following lines to it:

[version]
version=2.1
[browscap]
browser=*
platform=*
crawler=*
mobile=*

Place the browscap.ini file in the correct location.
Configure the browscap.dll file in the web server's configuration file.
Restart the web server to apply the changes.

Q: Can I use browscap.dll with other programming languages?

A: Yes, you can use browscap.dll with other programming languages, but you need to create a wrapper or interface to interact with the browscap.dll object. Here are some examples of programming languages that can be used with browscap.dll:

C#: You can use the System.Web namespace to interact with the browscap.dll object.
VB.NET: You can use the System.Web namespace to interact with the browscap.dll object.
PHP: You can use the php_browscap extension to interact with the browscap.dll object.

Q: Can I use browscap.dll with other web frameworks?

A: Yes, you can use browscap.dll with other web frameworks, but you need to create a wrapper or interface to interact with the browscap.dll object. Here are some examples of web frameworks that can be used with browscap.dll:

ASP.NET: You can use the System.Web namespace to interact with the browscap.dll object.
ASP.NET MVC: You can use the System.Web namespace to interact with the browscap.dll object.
PHP frameworks: You can use the php_browscap extension to interact with the browscap.dll object.

Q: Can I use browscap.dll with other databases?

A: Yes, you can use browscap.dll with other databases, but you need to create a wrapper or interface to interact with the browscap.dll object. Here are some examples of databases that can be used with browscap.dll:

SQL Server: You can use the System.Data.SqlClient namespace to interact with the browscap.dll object.
MySQL: You can use the php_mysqli extension to interact with the browscap.dll object.
Oracle: You can use the php_oci8 extension to interact with the browscap.dll object.