private void button_Copy3_Click(object sender, RoutedEventArgs e)
        {
            conn.Open();
            Staff           staInstance = new BookStore.Staff();
            StaffManagement staM        = new BookStore.StaffManagement();
            //查询结果:true--查询到,false--未查询到
            bool iRes = staM.InquireStaffInfo(textBox_Copy11.Text, staInstance, conn);

            if (iRes == true)
            {
                DateTime dt  = Convert.ToDateTime(staInstance.Sta_birth);
                DateTime dt2 = Convert.ToDateTime(staInstance.Sta_sign_date);

                textBox2.Text = staInstance.Sta_name;
                textBox3.Text = staInstance.Sta_gender;
                textBox6.Text = staInstance.Sta_address;
                textBox4.Text = staInstance.Sta_tele;
                textBox5.Text = Convert.ToString(dt.Year) + "/" + Convert.ToString(dt.Month) + "/" + Convert.ToString(dt.Day);
                textBox7.Text = Convert.ToString(dt2.Year) + "/" + Convert.ToString(dt2.Month) + "/" + Convert.ToString(dt2.Day);


                string st = "";
                if (staInstance.Sta_on_job == "Yes")
                {
                    st = "在职";
                }
                if (staInstance.Sta_on_job == "No")
                {
                    st = "离职";
                }
                textBox7_Copy3.Text = st;
                string str = "";
                if (staInstance.Po_title == "Cashier")
                {
                    str = "销售管理";
                }
                if (staInstance.Po_title == "Clerk")
                {
                    str = "库存管理";
                }
                if (staInstance.Po_title == "Manager")
                {
                    str = "管理员";
                }

                textBox7_Copy2.Text = str;
            }
            else
            {
                //*****************************未查询到,弹框!
            }
        }