C# 根据主窗体的位置弹窗信息窗体一直保持在主窗体中间

 Point p = this.Location;
            Form2 form2 = new Form2(p);

            int l2 = this.Width/2 - form2.Width / 2;
            int t2 = this.Height/2 - form2.Height / 2;
            int l = p.X + l2;
            int t = p.Y +t2;
            form2.Location = new Point(l, t);
            form2.ShowDialog();