如何以编程方式确定Windows任务栏是否隐藏？

Question

我需要知道Windows任务栏是否隐藏.我相信没有.NET方法可以做到这一点,而且我也遇到了很多"如何隐藏和显示任务栏"的样本,但我没有看到任何基于我正在寻找的东西.我不熟悉Windows API,因此我发现很难理解传统的Windows代码.有人可以指导我一篇文章或输入代码,告诉我是否隐藏了任务栏的当前状态？我在C#编码.

谢谢.

Answer 1

winSharp93提供了一个帮助类(" 查找任务栏的大小(和位置) ")似乎有效.它使用Win32的SHAppBarMessage函数.

这是他博客上的代码(有少量补充):

using System;
using System.Drawing;
using System.Runtime.InteropServices;

namespace TaskbarTest
{
    public enum TaskbarPosition
    {
        Unknown = -1,
        Left,
        Top,
        Right,
        Bottom,
    }

    public sealed class Taskbar
    {
        private const string ClassName = "Shell_TrayWnd";

        public Rectangle Bounds {
            get;
            private set;
        }
        public TaskbarPosition Position {
            get;
            private set;
        }
        public Point Location {
            get {
                return this.Bounds.Location;
            }
        }
        public Size Size {
            get {
                return this.Bounds.Size;
            }
        }
        //Always returns false under Windows 7
        public bool AlwaysOnTop {
            get;
            private set;
        }
        public bool AutoHide {
            get;
            private set;
        }

        public Taskbar() {
            IntPtr taskbarHandle = User32.FindWindow(Taskbar.ClassName, null);

            APPBARDATA data = new APPBARDATA();
            data.cbSize = (uint)Marshal.SizeOf(typeof(APPBARDATA));
            data.hWnd = taskbarHandle;
            IntPtr result = Shell32.SHAppBarMessage(ABM.GetTaskbarPos, ref data);
            if (result == IntPtr.Zero)
                throw new InvalidOperationException();

            this.Position = (TaskbarPosition)data.uEdge;
            this.Bounds = Rectangle.FromLTRB(data.rc.left, data.rc.top, data.rc.right, data.rc.bottom);

            data.cbSize = (uint)Marshal.SizeOf(typeof(APPBARDATA));
            result = Shell32.SHAppBarMessage(ABM.GetState, ref data);
            int state = result.ToInt32();
            this.AlwaysOnTop = (state & ABS.AlwaysOnTop) == ABS.AlwaysOnTop;
            this.AutoHide = (state & ABS.Autohide) == ABS.Autohide;
        }
    }

    public enum ABM : uint
    {
        New = 0x00000000,
        Remove = 0x00000001,
        QueryPos = 0x00000002,
        SetPos = 0x00000003,
        GetState = 0x00000004,
        GetTaskbarPos = 0x00000005,
        Activate = 0x00000006,
        GetAutoHideBar = 0x00000007,
        SetAutoHideBar = 0x00000008,
        WindowPosChanged = 0x00000009,
        SetState = 0x0000000A,
    }

    public enum ABE : uint
    {
        Left = 0,
        Top = 1,
        Right = 2,
        Bottom = 3
    }

    public static class ABS
    {
        public const int Autohide = 0x0000001;
        public const int AlwaysOnTop = 0x0000002;
    }

    public static class Shell32
    {
        [DllImport("shell32.dll", SetLastError = true)]
        public static extern IntPtr SHAppBarMessage(ABM dwMessage, [In] ref APPBARDATA pData);
    }

    public static class User32
    {
        [DllImport("user32.dll", SetLastError = true)]
        public static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
    }

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

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

作者声称它适用于他的Windows 7机器,它似乎可以在我的XP Pro机器上运行.

以下是您可以使用它的方法:

    Taskbar tb = new Taskbar();
    Console.WriteLine("w:{0}, h:{1} - hide:{2}", tb.Size.Width, tb.Size.Height, tb.AutoHide);

其中:tb.Size.Width和tb.Size.Height返回任务栏的宽度和高度,如果任务栏被隐藏,则tb.AutoHide返回true,否则返回false.