自由调整大小句柄无边框C#

Question

我正在尝试制作从工具栏中弹出的无边框表单.我希望用户能够抓住右下角("调整大小句柄")并能够调整表单大小,但无法以任何其他方式调整表单大小或重新定位.

我听说我可以拦截WM_NCHITTEST发送到表单的消息,并设置其结果HTBOTTOMRIGHT,让操作系统处理重新调整表单的大小,就像它有一个相当大的框架一样.我的想法是检测鼠标指针是否已进入我在角落中定义的框,如果它已经,则返回HTBOTTOMRIGHT结果.

这并不像我预期的那样有效.我能够拦截消息,但似乎只有当用户将鼠标光标放在窗体的1px粗边框上时才会发送消息.这意味着它可以按照我想要的方式工作,如果你将光标精确地放在右下角的边缘上.

这是我的WndProc覆盖:

protected override void WndProc(ref Message m)
{
    const UInt32 WM_NCHITTEST = 0x0084;
    const UInt32 HTBOTTOMRIGHT = 17;
    const int RESIZE_HANDLE_SIZE = 40;
    bool handled = false;
    if (m.Msg == WM_NCHITTEST)
    {
        Size formSize = this.Size;
        Point screenPoint = new Point(m.LParam.ToInt32());
        Point clientPoint = this.PointToClient(screenPoint);
        Rectangle hitBox = new Rectangle(formSize.Width - RESIZE_HANDLE_SIZE, formSize.Height - RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE);
        if (hitBox.Contains(clientPoint))
        {
            m.Result = (IntPtr)HTBOTTOMRIGHT;
            handled = true;
        }
    }

    if (!handled)
        base.WndProc(ref m);
}

我做错了什么或者有更好的方法来做我想做的事情吗？

非常感谢.

Answer 1

我正在寻找类似的东西,安东的代码是一个很好的基础.这就是我最终要从各方面调整工作量.我不确定这Dictionary是存放热门音箱的最佳方式,但我想这并不重要.

而且由于我的表单充满了使用Fill as Dock参数的控件,我只需添加一个5px填充,Form以便它可以很好地工作.

protected override void WndProc(ref Message m)
{
    const UInt32 WM_NCHITTEST = 0x0084;
    const UInt32 WM_MOUSEMOVE = 0x0200;

    const UInt32 HTLEFT = 10;
    const UInt32 HTRIGHT = 11;
    const UInt32 HTBOTTOMRIGHT = 17;
    const UInt32 HTBOTTOM = 15;
    const UInt32 HTBOTTOMLEFT = 16;
    const UInt32 HTTOP = 12;
    const UInt32 HTTOPLEFT = 13;
    const UInt32 HTTOPRIGHT = 14;

    const int RESIZE_HANDLE_SIZE = 10;
    bool handled = false;
    if (m.Msg == WM_NCHITTEST || m.Msg == WM_MOUSEMOVE)
    {
        Size formSize = this.Size;
        Point screenPoint = new Point(m.LParam.ToInt32());
        Point clientPoint = this.PointToClient(screenPoint);

        Dictionary<UInt32, Rectangle> boxes = new Dictionary<UInt32, Rectangle>() {
            {HTBOTTOMLEFT, new Rectangle(0, formSize.Height - RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE)},
            {HTBOTTOM, new Rectangle(RESIZE_HANDLE_SIZE, formSize.Height - RESIZE_HANDLE_SIZE, formSize.Width - 2*RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE)},
            {HTBOTTOMRIGHT, new Rectangle(formSize.Width - RESIZE_HANDLE_SIZE, formSize.Height - RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE)},
            {HTRIGHT, new Rectangle(formSize.Width - RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE, formSize.Height - 2*RESIZE_HANDLE_SIZE)},
            {HTTOPRIGHT, new Rectangle(formSize.Width - RESIZE_HANDLE_SIZE, 0, RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE) },
            {HTTOP, new Rectangle(RESIZE_HANDLE_SIZE, 0, formSize.Width - 2*RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE) },
            {HTTOPLEFT, new Rectangle(0, 0, RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE) },
            {HTLEFT, new Rectangle(0, RESIZE_HANDLE_SIZE, RESIZE_HANDLE_SIZE, formSize.Height - 2*RESIZE_HANDLE_SIZE) }
        };

        foreach (KeyValuePair<UInt32, Rectangle> hitBox in boxes)
        {
            if (hitBox.Value.Contains(clientPoint))
            {
                m.Result = (IntPtr) hitBox.Key;
                handled = true;
                break;
            }
        }
    }

    if (!handled)
        base.WndProc(ref m);
}