#region Using directives
using System;
using System.Text;
using System.Collections;
using System.Runtime.InteropServices;
#endregion

/// <summary>
/// A sample application for capturing current Internet Explorer windows' URLs.
/// By Stanimir Stoyanov, www.stoyanoff.info
/// 
/// NOTE: Tested with Internet Explorer 6 only.
/// </summary>
class IEURLCrawler
{
	#region Constants
	// Define the necessary constants.
	private const string IEClassName = "IEFrame";
	private static readonly IntPtr WM_GETTEXT = new IntPtr(13);
	#endregion

	#region Entry Point
	[STAThread]
	static void Main(string[] args)
	{
		IntPtr hWnd = IntPtr.Zero;

		// Initialize the Windows Enumerating Filter: IE Frame Windows only.
		SafeNativeMethods.EnumerateWindowsFilters enumWindFilter;
		enumWindFilter.inCaption = null;
		enumWindFilter.inClass = IEClassName;
		enumWindFilter.windowHandles = new ArrayList();

		SafeNativeMethods.EnumWindows(new SafeNativeMethods.EnumWindowsProc(WindowEnum), ref enumWindFilter);

		// The IE Window Hierarchy is: (NOTE: IE6-tested only!)
		// IEFrame -> WorkerW -> ReBarWindow32 -> ComboBoxEx32 (-> ComboBox -> Edit).
		foreach (IntPtr chWnd in enumWindFilter.windowHandles)
		{
			hWnd = SafeNativeMethods.FindWindowEx(chWnd, IntPtr.Zero, "WorkerW", null);
			if (hWnd != IntPtr.Zero)
			{
				hWnd = SafeNativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "ReBarWindow32", null);
				if (hWnd != IntPtr.Zero)
				{
					hWnd = SafeNativeMethods.FindWindowEx(hWnd, IntPtr.Zero, "ComboBoxEx32", null);
					if (hWnd != IntPtr.Zero)
					{
						// Get ahold of the URL...
						StringBuilder sb = new StringBuilder(256);
						SafeNativeMethods.SendMessage(hWnd, WM_GETTEXT, new IntPtr(sb.Capacity), sb);

						// ... and output it.
						Console.WriteLine(sb.ToString());
					}
				}
			}
		}

		// Clean up.
		enumWindFilter.windowHandles.Clear();
		enumWindFilter.windowHandles = null;

		// Let the Console Window hold on.
		Console.WriteLine("\r\nPress Return to exit.");
		Console.Read();
	}
	#endregion

	#region Window Enumerating Procedure.
	// The Window Enumerating procedure (filter non-IE windows).
	private static int WindowEnum(
		IntPtr hWnd,
		ref SafeNativeMethods.EnumerateWindowsFilters lParam)
	{
		StringBuilder sb = new StringBuilder(256);
		SafeNativeMethods.GetClassName(hWnd, sb, sb.Capacity);

		if (lParam.inClass != null)
		{
			if (sb.ToString() == lParam.inClass)
				lParam.windowHandles.Add(hWnd);
		}
		else
		{
			lParam.windowHandles.Add(hWnd);
		}
		return 1;
	}
	#endregion

	#region Win32
	// This Class defines the Win32 P/Invoke functions that we will use.
	class SafeNativeMethods
	{
		private const string User32 = "user32.dll";

		[StructLayout(LayoutKind.Sequential)]
		public struct EnumerateWindowsFilters
		{
			public IList windowHandles;
			public string inCaption;
			public string inClass;
		}

		[DllImport(User32, EntryPoint="GetClassNameW", CharSet = CharSet.Unicode, SetLastError = true)]
		public static extern IntPtr GetClassName(
			IntPtr hWnd,
			[MarshalAs(UnmanagedType.LPWStr)] StringBuilder lpClassName,
			int nMaxCount
		  );

		[DllImport(User32, EntryPoint = "SendMessageW", CharSet = CharSet.Unicode, SetLastError = true)]
		public static extern IntPtr SendMessage(
			IntPtr hWnd,
			IntPtr Msg,
			IntPtr wParam,
			[MarshalAs(UnmanagedType.LPWStr)] StringBuilder lParam
		  );

		[DllImport(User32)]
		public static extern IntPtr FindWindowEx(
			IntPtr hWndParent,
			IntPtr hWndChild,
			string WndClass,
			string WndTitle
			);

		[DllImport(User32)]
		public extern static int EnumWindows(
			EnumWindowsProc lpEnumFunc,
			ref EnumerateWindowsFilters lParam
			);

		public delegate int EnumWindowsProc(
			IntPtr hwnd,
			ref SafeNativeMethods.EnumerateWindowsFilters lParam
			);
	}
	#endregion
}