protected void Page_Load(object sender, EventArgs e)
 {
     if (Session["EmployeePKID"].ToString() != "" && long.TryParse(Session["EmployeePKID"].ToString(), out _PKID))
     {
         _PKID = long.Parse(Session["EmployeePKID"].ToString());
         _employee = new EmployeeClass(_PKID);
         if (!Page.IsPostBack)
         {
             displayRecord();  
         }
     }
     else
     {
         _employee = new EmployeeClass();
     }
     
     
 }
 protected void btnDelete_Click(object sender, EventArgs e)
 {
     if (Session["EmployeePKID"].ToString() != "" && long.TryParse(Session["EmployeePKID"].ToString(), out _PKID))
     {
         _PKID = long.Parse(Session["EmployeePKID"].ToString());
         _employee = new EmployeeClass(_PKID);
         _employee.deleteRecord(_PKID);
         Session["EmployeePKID"] = "";
     }
     fillGridView();
 }