How to Hide the Resize cursor in WPF?

Question

I have a WPF application. Which is Re sizable. But I want to hide the Resize cursor on left edges of the Window and some specific position of the window. Someone suggest me to call the Win32 API but I don't know how to do that.

Answer 1

Another similar way is to test the return of DefWindowProc in WM_NCHITTEST

                int nRet = DefWindowProc(hWnd, WM_NCHITTEST, 0, lParam);
                switch (nRet)
                {
                    case HTLEFT:
                    case HTTOP:
                    case HTBOTTOM:
                    case HTRIGHT:
                    case HTBOTTOMLEFT:
                    case HTBOTTOMRIGHT:
                    case HTTOPLEFT:
                    case HTTOPRIGHT:
                        {
                            handled = true;
                            return new IntPtr(HTNOWHERE);
                        }
                }

with :

        [DllImport("User32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        public static extern int DefWindowProc(IntPtr hWnd, int msg, int wParam, IntPtr lParam);

Answer 2

Try adding these functions to your window:

protected override void OnSourceInitialized( EventArgs e )
{
    base.OnSourceInitialized( e );
    HwndSource s = (HwndSource)PresentationSource.FromVisual( this );
    s.AddHook( WndProc );
}

private IntPtr WndProc( IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled )
{
    const int WM_NCHITTEST = 0x0084;
    const int HTNOWHERE = 0;

    switch( msg )
    {
    case WM_NCHITTEST:

        int x = lParam.ToInt32( ) & 0xffff;
        int y = lParam.ToInt32( ) >> 16;

        var p = new Point( x, y );
        p = PointFromScreen( p );

        if( p.X < SystemParameters.ResizeFrameVerticalBorderWidth )
        {
            handled = true;

            return new IntPtr( HTNOWHERE );
        }
        break;
    }

    return IntPtr.Zero;
}

It disable the resizing at left. Add more tests for p.X and p.Y (the local coordinates of mouse pointer) according to your needs.