MdiContainer

        /// <summary>
        /// 显示form
        /// </summary>
        /// <param name="form">要显示的form</param>
        /// <param name="canClose">是否将其他form关闭</param>
        private void ShowForm(Form form, bool canClose)
        {
            foreach (Form mdiChild in MdiChildren)
            {
                bool b = mdiChild.GetType() == form.GetType();
                if (b)
                {
                    form.Close();
                    mdiChild.Focus();
                    return;
                }
                if (canClose)
                {
                    mdiChild.Close();
                }
            }
            form.MdiParent = this;
            form.ControlBox = false;
            form.WindowState = FormWindowState.Maximized;
            form.Show();
        }