.net - Retrieve current URL from C# windows forms application

Question

I have been designing a program using Visual C# and have came across an issue with making my program interact with web browsers. Basically what I need is to retrieve the URL address from a web browser (Internet Explorer, Firefox, Chrome etc...).

I figured this wouldn't be too difficult of a task, but after days and days of research and tests, it seems almost impossible! Thus far, I have come across this...

Get Firefox URL?

Which has the code below:

using NDde.Client;
Class Test
{
    public static string GetFirefoxURL()
    {
        DdeClient dde = new DdeClient("Firefox", "WWW_GetWindowInfo");
        dde.Connect();
        string url = dde.Request("URL", int.MaxValue);
        dde.Disconnect();
        return url;
    }
}

Which is perfect for Firefox, but for some reason I cannot get it to work with anything else. I have changed the portion of the code that says "Firefox" to "Iexplore" like I found all over the internet, along with trying other forms of expressing Internet Explorer, and I get the following error:

"Client failed to connect to "IExplorer|WWW_GetWindowInfo", Make sure the server application is running and that it supports the specified service name and topic name pair"

Any help on the issue would be much appreciated as it has become quite a task to figure out.

Answer 1

Here is a code based on Microsoft UI Automation:

public static string GetChromeUrl(Process process)
{
    if (process == null)
        throw new ArgumentNullException("process");

    if (process.MainWindowHandle == IntPtr.Zero)
        return null;

    AutomationElement element = AutomationElement.FromHandle(process.MainWindowHandle);
    if (element == null)
        return null;

    AutomationElement edit = element.FindFirst(TreeScope.Children, new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Edit));
    return ((ValuePattern)edit.GetCurrentPattern(ValuePattern.Pattern)).Current.Value as string;
}

public static string GetInternetExplorerUrl(Process process)
{
    if (process == null)
        throw new ArgumentNullException("process");

    if (process.MainWindowHandle == IntPtr.Zero)
        return null;

    AutomationElement element = AutomationElement.FromHandle(process.MainWindowHandle);
    if (element == null)
        return null;

    AutomationElement rebar = element.FindFirst(TreeScope.Children, new PropertyCondition(AutomationElement.ClassNameProperty, "ReBarWindow32"));
    if (rebar == null)
        return null;

    AutomationElement edit = rebar.FindFirst(TreeScope.Subtree, new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Edit));

    return ((ValuePattern)edit.GetCurrentPattern(ValuePattern.Pattern)).Current.Value as string;
}

public static string GetFirefoxUrl(Process process)
{
    if (process == null)
        throw new ArgumentNullException("process");

    if (process.MainWindowHandle == IntPtr.Zero)
        return null;

    AutomationElement element = AutomationElement.FromHandle(process.MainWindowHandle);
    if (element == null)
        return null;

    AutomationElement doc = element.FindFirst(TreeScope.Subtree, new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Document));
    if (doc == null)
        return null;

    return ((ValuePattern)doc.GetCurrentPattern(ValuePattern.Pattern)).Current.Value as string;
}

You can use the UI Spy tool to understand the visual hierarchy for all 3 browsers. You may need to adapt things to make sure it really work in your specific cases, but you should get the general idea with these samples.

And an example that dumps all urls for all the 3 types of process (IE, FF, CH) currently running in the system:

static void Main(string[] args)
{
    foreach (Process process in Process.GetProcessesByName("firefox"))
    {
        string url = GetFirefoxUrl(process);
        if (url == null)
            continue;

        Console.WriteLine("FF Url for '" + process.MainWindowTitle + "' is " + url);
    }

    foreach (Process process in Process.GetProcessesByName("iexplore"))
    {
        string url = GetInternetExplorerUrl(process);
        if (url == null)
            continue;

        Console.WriteLine("IE Url for '" + process.MainWindowTitle + "' is " + url);
    }

    foreach (Process process in Process.GetProcessesByName("chrome"))
    {
        string url = GetChromeUrl(process);
        if (url == null)
            continue;

        Console.WriteLine("CH Url for '" + process.MainWindowTitle + "' is " + url);
    }
}