Getting Current Browser URL with VB.NET

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• Download source - 2.23 KB

Introduction

This article explains how you can get the current URL from your browser with VB.NET. The demo program demonstrates this for Windows Internet Explorer and Google Chrome.

Background

For one of my VB.NET programs, I wanted to get the current browser URL; of course I can copy and paste it, but if the program can get it for me, all the better. So I searched the internet and found numerous "solutions" but they were all either written in C or did not work (at least not for me). After reading various forums, I decided to adapt one of these solutions and managed to get the URL from Internet Explorer and from Chrome; attempts to get the URL from Firefox were unsuccessful.

My development configuration is: Microsoft Visual Basic 2008 Express, Windows7 Home Premium 64 bits, IE9, Chrome 11.0.696.68, Firefox 4. The code has also been tested on Vista 32 bits. The basic ideas and forum suggestions are referenced in the code.

The code is in the CurrentUrl.vb module, which you can add to your project. In your code, you should first verify that the browser (Internet Explorer or Chrome) is available.

For example:

...
Dim appName As String = "iexplore"
Dim proc As System.Diagnostics.Process = GetBrowser(appName)
...
Private Function GetBrowser(ByVal appName) As System.Diagnostics.Process
    Dim pList() As System.Diagnostics.Process =  
 System.Diagnostics.Process.GetProcessesByName(appName)
    For Each proc As System.Diagnostics.Process In pList
        If proc.ProcessName = appName Then
            Return proc
        End If
    Next
    Return Nothing
End Function
...	

If the browser process is returned, call the GetCurrentUrl function in CurrentUrl.vb with these parameters:

• The browser window handle: proc.MainWindowHandle
• The browser name: "Windows Internet Explorer" or "Google Chrome"
• The classname of the window to look for: "Edit" for IE, "Chrome_AutocompleteEditView" for Chrome
• (Optional) A combobox to get a "treeview" of the browser windows up to the target window; pass Nothing if you don't want this

...
If proc IsNot Nothing Then
    Dim browserName as string = "Windows Internet Explorer"
    Dim className as String = "Edit" 
    Dim s As String = 
GetCurrentUrl(proc.MainWindowHandle, browserName, className, ComboBox1)
    If s <> "" Then
        TextBox1.Text = s
        ComboBox1.SelectedIndex = 0 'Window list
    Else
        Label1.Text = "Current URL is not available"
    End If
Else
    Label1.Text = browserName & " is not available"
end If
...

Inside CurrentUrl.vb

This module contains a simple overview, references to the sources on which it is based, and definitions of the required Windows functions and constants, as well as some private variables.

GetCurrentUrl is the only public function; it calls the private EnumWindows function to get window handles until it finds the browser window and then look for the child window with the URL. The URL string is returned to your program.

Points of Interest

In the referenced sources, the search for the target window starts from the top window (Intptr.Zero) and it returns a list of URLs. My approach starts from the browser window (proc.MainWindowHandle); I used GetBrowser and debugged CurrentUrl until I found the target window with the appropriate classname to get only one URL. Unfortunately, this does not work for Firefox, which requires a completely different approach to get window handles (see Firefox Access).

History

• May 2011 - First release
• June 2011 - Source updated with Option Strict On