private void btManagerLogin_Click(object sender, EventArgs e)
        {
            string caption = "输入提示";

            //用户名或密码都不为空
            if (CheckInput())
            {
                //检索用户名密码都存在
                string message = string.Empty;
                if (CheckUser(ref message))
                {
                    Member member = new Member();
                    member.MemberId  = tbManagerID.Text.Trim();
                    member.MemberPwd = tbManagerPwd.Text.Trim();
                    //验证成功之后打开Manager的管理界面
                    ManagerMain mm = new ManagerMain();
                    this.Hide();//隐藏登陆窗体
                    mm.ShowDialog();
                    this.Close();
                }
                else
                {
                    MessageBox.Show(message, caption, MessageBoxButtons.OK, MessageBoxIcon.Warning);
                }
            }
        }
        private void btManagerLogin_Click(object sender, EventArgs e)
        {
            string caption = "输入提示";
            //用户名或密码都不为空
            if (CheckInput())
            {
                //检索用户名密码都存在
                string message = string.Empty;
                if (CheckUser(ref message))
                {
                    Member member = new Member();
                    member.MemberId = tbManagerID.Text.Trim();
                    member.MemberPwd = tbManagerPwd.Text.Trim();
                    //验证成功之后打开Manager的管理界面
                    ManagerMain mm = new ManagerMain();
                    this.Hide();//隐藏登陆窗体
                    mm.ShowDialog();
                    this.Close();

                }
                else
                {
                    MessageBox.Show(message ,caption ,MessageBoxButtons.OK,MessageBoxIcon.Warning);
                }
            }
        }