Taskbard | taskbarautohidernot - Toggle Taskbar Auto-Hide

This program demonstrates how to toggle the auto-hide functionality of the Windows taskbar using C# and Windows API calls.

Downloads: Why are tehere two versions? First was the console version (Taskbard) but to avoid the window flashing made it taskbardauthidernot a WINDOW-LESS app without any UX

What does it do?

Why does it exist?

It is doing is the same thing you can do from the Taskbar 'behavior' settings when you enable or disable "automatically hide the taskbar".
This little bit of code make it super simple to find the task bar and change that setting with just a single click that you can run from a shortcut or from a button on your stream deck.

How to use

What Versions are supported?

This is Developed using .Net and Windows 11 24H2 but its been tested and us used with both 11 23H2 and Windows 10 22H2.
If you dont have the .Net files installed you may be prompted to get them from Microsoft.

Overview

The program achieves the following:

Code

Below is the full source code written in C#:


using System;
using System.Runtime.InteropServices;

class Program
{
    private const int ABM_GETSTATE = 0x00000004;
    private const int ABM_SETAUTOHIDEBAREX = 0x0000000a;

    [DllImport("shell32.dll", CallingConvention = CallingConvention.StdCall)]
    private static extern uint SHAppBarMessage(uint dwMessage, ref APPBARDATA pData);

    [DllImport("user32.dll", SetLastError = true)]
    private static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

    [StructLayout(LayoutKind.Sequential)]
    private struct APPBARDATA
    {
        public uint cbSize;
        public IntPtr hWnd;
        public uint uCallbackMessage;
        public uint uEdge;
        public RECT rc;
        public int lParam;
    }

    [StructLayout(LayoutKind.Sequential)]
    private struct RECT
    {
        public int left;
        public int top;
        public int right;
        public int bottom;
    }

    static void Main()
    {
        try
        {
            IntPtr taskbarHandle = FindWindow("Shell_TrayWnd", null);
            if (taskbarHandle == IntPtr.Zero)
                throw new InvalidOperationException("Taskbar window not found.");

            uint screenEdge = 3; // Bottom edge
            bool newState = ToggleAutoHide(taskbarHandle, screenEdge);
            Console.WriteLine($"Auto-hide is now {(newState ? "enabled" : "disabled")}.");
        }
        catch (Exception ex)
        {
            Console.WriteLine($"Error: {ex.Message}");
        }
    }

    static bool ToggleAutoHide(IntPtr taskbarHandle, uint screenEdge)
    {
        APPBARDATA appBarData = new APPBARDATA
        {
            cbSize = (uint)Marshal.SizeOf(typeof(APPBARDATA)),
            hWnd = taskbarHandle,
            uEdge = screenEdge
        };

        // Check current auto-hide state
        bool isAutoHideEnabled = IsAutoHideEnabled(appBarData);

        appBarData.lParam = isAutoHideEnabled ? 0 : 1; // Toggle state
        uint result = SHAppBarMessage(ABM_SETAUTOHIDEBAREX, ref appBarData);

        if (result == 0)
        {
            throw new InvalidOperationException("Failed to toggle auto-hide state.");
        }

        return !isAutoHideEnabled; // Return the new state
    }

    static bool IsAutoHideEnabled(APPBARDATA appBarData)
    {
        uint state = SHAppBarMessage(ABM_GETSTATE, ref appBarData);
        return (state & 0x01) != 0; // Auto-hide flag
    }
}

GUI Code Alternative

Below is the GUI source code written in C#:

Alternative Approach: Issue: if you dont like the console window flashing here is another way to do it with a GUI app. 
		
using System;
using System.Runtime.InteropServices;

class Program
{
    private const int ABM_GETSTATE = 0x00000004;
    private const int ABM_SETAUTOHIDEBAREX = 0x0000000a;

    [DllImport("shell32.dll", CallingConvention = CallingConvention.StdCall)]
    private static extern uint SHAppBarMessage(uint dwMessage, ref APPBARDATA pData);

    [DllImport("user32.dll", SetLastError = true)]
    private static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

    [StructLayout(LayoutKind.Sequential)]
    private struct APPBARDATA
    {
        public uint cbSize;
        public IntPtr hWnd;
        public uint uCallbackMessage;
        public uint uEdge;
        public RECT rc;
        public int lParam;
    }

    [StructLayout(LayoutKind.Sequential)]
    private struct RECT
    {
        public int left;
        public int top;
        public int right;
        public int bottom;
    }

    [STAThread]
    static void Main()
    {
        try
        {
            // Prevents flashing console window
            IntPtr taskbarHandle = FindWindow("Shell_TrayWnd", null);
            if (taskbarHandle == IntPtr.Zero)
                throw new InvalidOperationException("Taskbar window not found.");

            uint screenEdge = 3; // Bottom edge
            bool newState = ToggleAutoHide(taskbarHandle, screenEdge);

            // Optional: Write output to a log file instead of using Console
            System.IO.File.AppendAllText("TaskbarToggleLog.txt", 
                $"Auto-hide is now {(newState ? "enabled" : "disabled")}. Timestamp: {DateTime.Now}\n");
        }
        catch (Exception ex)
        {
            // Handle errors silently or log them
            System.IO.File.AppendAllText("TaskbarToggleLog.txt", 
                $"Error: {ex.Message}. Timestamp: {DateTime.Now}\n");
        }
    }

    static bool ToggleAutoHide(IntPtr taskbarHandle, uint screenEdge)
    {
        APPBARDATA appBarData = new APPBARDATA
        {
            cbSize = (uint)Marshal.SizeOf(typeof(APPBARDATA)),
            hWnd = taskbarHandle,
            uEdge = screenEdge
        };

        // Check current auto-hide state
        bool isAutoHideEnabled = IsAutoHideEnabled(appBarData);

        appBarData.lParam = isAutoHideEnabled ? 0 : 1; // Toggle state
        uint result = SHAppBarMessage(ABM_SETAUTOHIDEBAREX, ref appBarData);

        if (result == 0)
        {
            throw new InvalidOperationException("Failed to toggle auto-hide state.");
        }

        return !isAutoHideEnabled; // Return the new state
    }

    static bool IsAutoHideEnabled(APPBARDATA appBarData)
    {
        uint state = SHAppBarMessage(ABM_GETSTATE, ref appBarData);
        return (state & 0x01) != 0; // Auto-hide flag
    }
}