//借书操作
 protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
 {
     DataKey keys = GridView1.DataKeys[e.RowIndex];
     string psid = keys.Value.ToString();
     Operation op = new Operation();
     //达到最大借阅量,借阅失败
     string employeeName = op.PSIDToName(psid);
     if(!op.Borrow(psid,Session["BID"].ToString()))
     {
         if (Session["lang"].ToString() == "zh-cn")
             Response.Write("<script>alert('借阅失败!" + employeeName + " 已经达到最大借阅量!');window.location.href='./Query_employee.aspx'</script>");
         else
             Response.Write("<script>alert('Borrow failed!"+employeeName+" already reach the MaxBorrowNumber!');window.location.href='./Query_employee.aspx'</script>");
     }
     //借阅成功
     else
     {
         if (Session["lang"].ToString() == "zh-cn")
             Response.Write("<script>alert('借阅成功!" + employeeName + " 还可以继续借阅 " + op.CanBorrowNum(psid) + " books.');window.location.href='./Query_employee.aspx'</script>");
         else
             Response.Write("<script>alert('Borrow success!" + employeeName + " still can borrow " + op.CanBorrowNum(psid) + " books.');window.location.href='./Query_employee.aspx'</script>");
     }
 }