I am working on the UI for an application using Windows Form. I made a resizable borderless form after consulting this question and this one as well.
But now, I have an issue in the maximized state, that is, if I move the mouse to the edge, I can still resize the form. How do I make the form Freeze in the maximized state to prevent this resizing?
Code to make form Borderless
protected override void WndProc(ref Message m)
{
const int RESIZE_HANDLE_SIZE = 10;
switch (m.Msg)
{
case 0x0084/*NCHITTEST*/ :
base.WndProc(ref m);
if ((int)m.Result == 0x01/*HTCLIENT*/)
{
Point screenPoint = new Point(m.LParam.ToInt32());
Point clientPoint = this.PointToClient(screenPoint);
if (clientPoint.Y <= RESIZE_HANDLE_SIZE)
{
if (clientPoint.X <= RESIZE_HANDLE_SIZE)
m.Result = (IntPtr)13/*HTTOPLEFT*/ ;
else if (clientPoint.X < (Size.Width - RESIZE_HANDLE_SIZE))
m.Result = (IntPtr)12/*HTTOP*/ ;
else
m.Result = (IntPtr)14/*HTTOPRIGHT*/ ;
}
else if (clientPoint.Y <= (Size.Height - RESIZE_HANDLE_SIZE))
{
if (clientPoint.X <= RESIZE_HANDLE_SIZE)
m.Result = (IntPtr)10/*HTLEFT*/ ;
else if (clientPoint.X < (Size.Width - RESIZE_HANDLE_SIZE))
m.Result = (IntPtr)2/*HTCAPTION*/ ;
else
m.Result = (IntPtr)11/*HTRIGHT*/ ;
}
else
{
if (clientPoint.X <= RESIZE_HANDLE_SIZE)
m.Result = (IntPtr)16/*HTBOTTOMLEFT*/ ;
else if (clientPoint.X < (Size.Width - RESIZE_HANDLE_SIZE))
m.Result = (IntPtr)15/*HTBOTTOM*/ ;
else
m.Result = (IntPtr)17/*HTBOTTOMRIGHT*/ ;
}
}
return;
}
base.WndProc(ref m);
}
protected override CreateParams CreateParams
{
get
{
CreateParams cp = base.CreateParams;
cp.Style |= 0x20000; // <--- use 0x20000
cp.ClassStyle |= 0x08;
return cp;
}
}
Code to quit,maximize/restore,minimize
private void button1_Click(object sender, EventArgs e)
{
Application.Exit();
}
private void button2_Click(object sender, EventArgs e)
{
if(this.WindowState==FormWindowState.Normal)
{
this.button2.Image = ((System.Drawing.Image)(Properties.Resources.Restore_Down));
this.MaximizedBounds = Screen.FromHandle(this.Handle).WorkingArea;
this.WindowState = FormWindowState.Maximized;
}
else if(this.WindowState == FormWindowState.Maximized)
{
this.WindowState = FormWindowState.Normal;
this.button2.Image = ((System.Drawing.Image)(Properties.Resources.Maximize));
}
}
private void button3_Click(object sender, EventArgs e)
{
this.WindowState = FormWindowState.Minimized;
}