Added Vanara.Windows.Taskbar class to get information on the Shell's taskbar.

Windows.Shell.Common/ShellData/TaskAgg.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -7,7 +8,32 @@ namespace Vanara.Windows.Shell
 {
 	internal static class TaskAgg
 	{
-		public static Task CompletedTask => Task.CompletedTask;
+#if !(NET46_OR_GREATER || NETSTANDARD1_2_OR_GREATER || NETCOREAPP)
+		private static Task _completedTask;
+#endif
+		public static Task CompletedTask
+		{
+			[MethodImpl(MethodImplOptions.AggressiveInlining)]
+			get
+			{
+#if NET46_OR_GREATER || NETSTANDARD1_2_OR_GREATER || NETCOREAPP
+				return Task.CompletedTask;
+#else
+				return _completedTask ??= FromResult(false);
+#endif
+			}
+		}
+
+		public static Task<TResult> FromResult<TResult>(TResult result)
+		{
+#if NET45_OR_GREATER || NETSTANDARD || NETCOREAPP
+			return Task.FromResult<TResult>(result);
+#else
+			var completionSource = new TaskCompletionSource<TResult>();
+			completionSource.TrySetResult(result);
+			return completionSource.Task;
+#endif
+		}
 
 		public static Task Run(Action action, CancellationToken cancellationToken)
 		{

Windows.Shell.Common/TaskBar/Taskbar.cs

@@ -1,18 +1,27 @@
 using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
 using Vanara.Extensions;
+using Vanara.InteropServices;
 using Vanara.PInvoke;
-
+using static Vanara.PInvoke.ComCtl32;
 using static Vanara.PInvoke.Shell32;
+using static Vanara.PInvoke.User32;
 
 namespace Vanara.Windows.Shell.TaskBar
 {
 	/// <summary>Provides information about and some control of the system taskbar.</summary>
 	public static class Taskbar
 	{
+		private const string NotifyWndClass = "TrayNotifyWnd";
+		private const string PagerWndClass = "SysPager";
+		private const string TaskbarWndClass = "Shell_TrayWnd";
+		private const string ToolbarWndClass = "ToolbarWindow32";
+
+		private static readonly Lazy<bool> isMinWin7 = new(() => PInvokeClientExtensions.IsPlatformSupported(PInvokeClient.Windows7));
 		private static bool autoHide, alwaysTop;
 		private static ABE edge;
 		private static HWND hwnd;
-		private static readonly Lazy<bool> isMinWin7 = new(() => PInvokeClientExtensions.IsPlatformSupported(PInvokeClient.Windows7));
 		private static RECT rect;
 
 		/// <summary>
@@ -69,13 +78,47 @@ namespace Vanara.Windows.Shell.TaskBar
 			get { GetPos(); return hwnd; }
 		}
 
+		/// <summary>Gets the tray icons.</summary>
+		/// <value>The tray icons.</value>
+		public static IEnumerable<TrayIcon> TrayIcons
+		{
+			get
+			{
+				const TBIF bif = TBIF.TBIF_BYINDEX | TBIF.TBIF_COMMAND | TBIF.TBIF_SIZE | TBIF.TBIF_STATE | TBIF.TBIF_STYLE | TBIF.TBIF_TEXT;
+
+				var hwnd = GetTrayWindow();
+				if (hwnd.IsNull) yield break;
+
+				using SafeCoTaskMemString strBuf = new(512);
+				TBBUTTONINFO defBI = new() { cbSize = (uint)Marshal.SizeOf(typeof(TBBUTTONINFO)), dwMask = bif, pszText = strBuf, cchText = strBuf.Capacity };
+
+				var cnt = SendMessage(hwnd, ToolbarMessage.TB_BUTTONCOUNT).ToInt32();
+				var badRes = new IntPtr(-1);
+				for (int i = 0; i < cnt; i++)
+				{
+					TBBUTTONINFO btnInf = defBI;
+					btnInf.cchText = strBuf.Capacity;
+					strBuf[0] = '\0';
+					Win32Error.ThrowLastErrorIf(SendMessage(hwnd, ToolbarMessage.TB_GETBUTTONINFOW, (IntPtr)i, ref btnInf), p => p == badRes);
+					yield return new(btnInf);
+				}
+			}
+		}
+
+		/// <summary>Broadcasts the "TaskbarCreated" message to all windows. This is generally used to refresh the taskbar icons.</summary>
+		public static void BroadcastTaskbarCreated()
+		{
+			var msg = Win32Error.ThrowLastErrorIf(RegisterWindowMessage("TaskbarCreated"), i => i == 0);
+			Win32Error.ThrowLastErrorIfFalse(SendNotifyMessage(HWND.HWND_BROADCAST, msg));
+		}
+
 		private static void GetPos()
 		{
 			APPBARDATA abd = new(default);
 			Win32Error.ThrowLastErrorIf(SHAppBarMessage(ABM.ABM_GETTASKBARPOS, ref abd), r => r == IntPtr.Zero);
 			rect = abd.rc;
 			edge = abd.uEdge;
-			hwnd = abd.hWnd == default ? User32.FindWindowEx(default, default, "Shell_TrayWnd", null) : abd.hWnd;
+			hwnd = abd.hWnd == default ? User32.FindWindowEx(default, default, TaskbarWndClass, null) : abd.hWnd;
 		}
 
 		private static void GetState()
@@ -86,6 +129,24 @@ namespace Vanara.Windows.Shell.TaskBar
 			alwaysTop = isMinWin7.Value || state.IsFlagSet(ABS.ABS_ALWAYSONTOP);
 		}
 
+		private static HWND GetTrayWindow()
+		{
+			HWND hwnd = FindWindow(TaskbarWndClass, "");
+			if (!hwnd.IsNull)
+			{
+				hwnd = FindWindowEx(hwnd, default, NotifyWndClass, "");
+				if (!hwnd.IsNull)
+				{
+					hwnd = FindWindowEx(hwnd, default, PagerWndClass, "");
+					if (!hwnd.IsNull)
+					{
+						return FindWindowEx(hwnd, default, ToolbarWndClass, null);
+					}
+				}
+			}
+			return hwnd;
+		}
+
 		private static void SetPos()
 		{
 			APPBARDATA abd = new(hwnd, 0, edge, rect);
@@ -103,4 +164,36 @@ namespace Vanara.Windows.Shell.TaskBar
 			SHAppBarMessage(ABM.ABM_SETSTATE, ref abd);
 		}
 	}
+
+	/// <summary></summary>
+	public class TrayIcon
+	{
+		internal TrayIcon(in TBBUTTONINFO inf)
+		{
+			CommandId = inf.idCommand;
+			ImageIdx = inf.iImage;
+			State = inf.fsState;
+			Style = inf.fsStyle;
+			Width = inf.cx;
+			Text = StringHelper.GetString(inf.pszText, CharSet.Unicode, inf.cchText);
+		}
+
+		/// <summary>Command identifier of the button.</summary>
+		public int CommandId { get; }
+
+		/// <summary>Image index of the button.</summary>
+		public int ImageIdx { get; }
+
+		/// <summary>State flags of the button. This can be one or more of the values listed in Toolbar Button States.</summary>
+		public TBSTATE State { get; }
+
+		/// <summary>Style flags of the button. This can be one or more of the values listed in Toolbar Control and Button Styles.</summary>
+		public ToolbarStyle Style { get; }
+
+		/// <summary>Address of a character buffer that contains or receives the button text.</summary>
+		public string Text { get; }
+
+		/// <summary>Width of the button, in pixels.</summary>
+		public ushort Width { get; }
+	}
 }