SetWindowPlacement 最大化时不会恢复到同一个监视器

Question

我有一个 Windows 窗体应用程序，它使用以下代码保存工具窗口的位置：

ToolWindow = new ToolViewer(TransformedResult);

ToolWindow.FormClosed += (_1, _2) =>
{
    this.ToolWindowPlacement = WindowPlacement.GetPlacement(ToolWindow.Handle);

    this.ToolWindow = null;
};
ToolWindow.Show();
WindowPlacement.SetPlacement(ToolWindow.Handle, ToolWindowPlacement);

它工作正常，除非工具窗口被最大化。如果它被最大化，窗口会继续显示在我的主监视器上，而不是在它关闭时最大化的那个。

WindowPlacement.cs：

// from http://blogs.msdn.com/b/davidrickard/archive/2010/03/09/saving-window-size-and-location-in-wpf-and-winforms.aspx
static class WindowPlacement
{
    [DllImport("user32.dll")]
    private static extern bool SetWindowPlacement(IntPtr hWnd, [In] ref WINDOWPLACEMENT lpwndpl);

    [DllImport("user32.dll")]
    private static extern bool GetWindowPlacement(IntPtr hWnd, out WINDOWPLACEMENT lpwndpl);

    private const int SW_SHOWNORMAL = 1;
    private const int SW_SHOWMINIMIZED = 2;

    public static void SetPlacement(IntPtr windowHandle, WINDOWPLACEMENT placement)
    {
        if (placement.length == 0)
            return;

        placement.length = Marshal.SizeOf(typeof(WINDOWPLACEMENT));
        placement.flags = 0;
        placement.showCmd = (placement.showCmd == SW_SHOWMINIMIZED ? SW_SHOWNORMAL : placement.showCmd);
        SetWindowPlacement(windowHandle, ref placement);
    }

    public static WINDOWPLACEMENT GetPlacement(IntPtr windowHandle)
    {
        WINDOWPLACEMENT placement = new WINDOWPLACEMENT();
        GetWindowPlacement(windowHandle, out placement);

        return placement;
    }
}

Answer 1

由于我不知道的原因，我不得不删除为表单设置的默认 WindowState 和 Maximized，以便让 SetWindowPlacement 将最大化的窗口恢复到正确的监视器。