如何以编程方式隐藏桌面图标？

Question

如何使用C#以编程方式显示/隐藏桌面图标？

我正在尝试创建一个使用小部件的替代桌面,我需要隐藏旧图标.

Answer 1

您可以使用Windows API执行此操作.以下是C#中将切换桌面图标的示例代码.

    [DllImport("user32.dll", SetLastError = true)] static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
    [DllImport("user32.dll", SetLastError = true)] static extern IntPtr GetWindow(IntPtr hWnd, GetWindow_Cmd uCmd);
    enum GetWindow_Cmd : uint
    {
        GW_HWNDFIRST = 0,
        GW_HWNDLAST = 1,
        GW_HWNDNEXT = 2,
        GW_HWNDPREV = 3,
        GW_OWNER = 4,
        GW_CHILD = 5,
        GW_ENABLEDPOPUP = 6
    }
    [DllImport("user32.dll", CharSet = CharSet.Auto)] static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);

    private const int WM_COMMAND = 0x111;

    static void ToggleDesktopIcons()
    {
        var toggleDesktopCommand = new IntPtr(0x7402);
        IntPtr hWnd = GetWindow(FindWindow("Progman", "Program Manager"), GetWindow_Cmd.GW_CHILD);
        SendMessage(hWnd, WM_COMMAND, toggleDesktopCommand, IntPtr.Zero);
    }

这会向Progman的SHELLDLL_DefView子窗口发送一条消息,告诉它切换它唯一的子项"FolderView"的可见性(通过添加或删除WS_VISIBLE样式)."FolderView"是包含图标的实际窗口.

要测试图标是否可见,可以使用GetWindowInfo函数查询WS_VISIBLE样式,如下所示:

    [return: MarshalAs(UnmanagedType.Bool)]
    [DllImport("user32.dll", SetLastError = true)]
    private static extern bool GetWindowInfo(IntPtr hwnd, ref WINDOWINFO pwi);

    [StructLayout(LayoutKind.Sequential)]
    public struct RECT
    {
        private int _Left;
        private int _Top;
        private int _Right;
        private int _Bottom;
    }

    [StructLayout(LayoutKind.Sequential)]
    struct WINDOWINFO
    {
        public uint cbSize;
        public RECT rcWindow;
        public RECT rcClient;
        public uint dwStyle;
        public uint dwExStyle;
        public uint dwWindowStatus;
        public uint cxWindowBorders;
        public uint cyWindowBorders;
        public ushort atomWindowType;
        public ushort wCreatorVersion;

        public WINDOWINFO(Boolean? filler)
            : this()   // Allows automatic initialization of "cbSize" with "new WINDOWINFO(null/true/false)".
        {
            cbSize = (UInt32)(Marshal.SizeOf(typeof(WINDOWINFO)));
        }

    }

这是一个调用上面代码的函数,如果窗口可见则返回true,否则返回false.

    static bool IsVisible()
    {
        IntPtr hWnd = GetWindow(GetWindow(FindWindow("Progman", "Program Manager"), GetWindow_Cmd.GW_CHILD), GetWindow_Cmd.GW_CHILD);
        WINDOWINFO info = new WINDOWINFO();
        info.cbSize = (uint)Marshal.SizeOf(info);
        GetWindowInfo(hWnd, ref info);
        return (info.dwStyle & 0x10000000) == 0x10000000;
    }

Windows API代码以及有关窗口样式的更多信息可以在这里找到:http://www.pinvoke.net/default.aspx/user32/GetWindowInfo.html

Answer 2

尽管当我尝试 Ondrej Balas 的回答时这已经很老了，但我发现这个解决方案的一个问题是，如果使用 ToggleDesktop 命令显示桌面（如果启用了壁纸旋转），它就不起作用。

在这两种情况下，作为 ToggleDesktopIcons 函数中 toggleDesktopCommand 接收者的 SHELLDLL_DefView 窗口不是“程序管理器”窗口的子窗口，而是“WorkerW”窗口的子窗口。（请参阅WinApi - 如何获取 SHELLDLL_DefView和Windows桌面 ListView 句柄。

基于这些并基于 Ondrej Balas 的早期答案，将 ToggleDesktopIcons 函数更改为：

static void ToggleDesktopIcons()
{
    var toggleDesktopCommand = new IntPtr(0x7402);
    SendMessage(GetDesktopSHELLDLL_DefView(), WM_COMMAND, toggleDesktopCommand, IntPtr.Zero);
}

并添加一个 GetDesktopSHELLDLL_DefView 函数：

    [DllImport("user32.dll", SetLastError = true)]
    public static extern IntPtr FindWindowEx(IntPtr parentHandle, IntPtr childAfter, string className, string windowTitle);
    [DllImport("user32.dll", SetLastError = false)]
    static extern IntPtr GetDesktopWindow();

    static IntPtr GetDesktopSHELLDLL_DefView()
    {
        var hShellViewWin = IntPtr.Zero;
        var hWorkerW = IntPtr.Zero;

        var hProgman = FindWindow("Progman", "Program Manager");
        var hDesktopWnd = GetDesktopWindow();

        // If the main Program Manager window is found
        if (hProgman != IntPtr.Zero)
        {
            // Get and load the main List view window containing the icons.
            hShellViewWin = FindWindowEx(hProgman, IntPtr.Zero, "SHELLDLL_DefView", null);
            if (hShellViewWin == IntPtr.Zero)
            {
                // When this fails (picture rotation is turned ON, toggledesktop shell cmd used ), then look for the WorkerW windows list to get the
                // correct desktop list handle.
                // As there can be multiple WorkerW windows, iterate through all to get the correct one
                do
                {
                    hWorkerW = FindWindowEx(hDesktopWnd, hWorkerW, "WorkerW", null);
                    hShellViewWin = FindWindowEx(hWorkerW, IntPtr.Zero, "SHELLDLL_DefView", null);
                } while (hShellViewWin == IntPtr.Zero && hWorkerW != IntPtr.Zero);
            }
        }
        return hShellViewWin;
    }

现在，无论桌面切换或墙纸旋转如何，ToggleDesktopIcons 都应始终有效。

作为参考，这是我的切换桌面功能，导致原始 ToggleDesktopIcons 功能出现问题

static public void ToggleDesktop(object sender, EventArgs e)
        {
            var shellObject = new Shell32.Shell();
            shellObject.ToggleDesktop();
        }

响应 James M，此函数返回当前状态：

bool IconsVisible()
{
    var hWnd = GetDesktopListView();
    var info = new User32.WINDOWINFO(null);
    User32.GetWindowInfo(hWnd, ref info);
    return (info.dwStyle & User32.WindowStyle.WS_VISIBLE) == User32.WindowStyle.WS_VISIBLE;
}