I want to detect when MouseButtons.Ri ght MouseButton.Mid dle are pusheds at the same time.

I have this
Code:
 
private void SceneView_MouseMove(object sender, MouseEventArgs e)
{
vMouseOld.x = vMouse.x;
vMouseOld.y = vMouse.y;
vMouse.x = e.X;
vMouse.y = e.Y - toolStrip1.Size.Height;
 switch (e.Button) 
            {
                case  MouseButtons.Right:   camera.yaw((vMouse.x
...