How Do I Display Error Or Successful Message After Data Inse

namespace CTP.HRMS.WebApp.Forms {     public partial class EmployeeAbsentForm : PageBase     {         protected override string ModuleName         {             get             {                 return "EmployeeAbsentForm";             }         }           private Employee _employee;         private Employee Employee         {             get             {                 if (_employee == null)                 {                     if (Request.QueryString["id"] != null)                     {                         _employee = _service.GetEmployee(Request.QueryString["id"].ToString());                     }                       if (_employee == null)                         _employee = new Employee();                 }                 return _employee;             }         }           protected void Page_Load(object sender, EventArgs e)         {             if (!MyUser.CanAccess.AbsentRecord)             {                 Redirect("/Forms/Redirected.aspx", "You do not have access to this page");             }               if (!Page.IsPostBack)             {                 Page.Header.Title = "Please Enter New Absent Record:";                 BindData();                 // PopulateData();             }         }           protected void BindData()         {             // Fill all Dropdowns             ddlRollNo.Bind(_service.GetAllEmployee(), "IdName", "Id");             ddlRank.Bind(_service.GetAllRank());         }           //protected void PopulateData()         //{         //    if ( Employee.Id != null)         //    {          //       // txtName.Text = Employee.Name;         //        EmployeeAbsent empAbsent = new EmployeeAbsent();          //        txtRollNo.Text = Employee.Id;         //        ddlRank.SelectedValue =          //        txtStartDate.Text = empAbsent.StartDate.ToString();         //        txtEndDate.Text = empAbsent.EndDate.ToString();         //        txtDurtion.Text = empAbsent.Durtion;         //        txtReason.Text = empAbsent.Reason;          //    }         //}            protected void btnSubmit_Click(object sender, EventArgs e)         {             try             {                 string[] temp = txtstartTime.Value.Split(new char[] { ' ', ':' });                 DateTime startDate = SafeConvert.ToDateTime(txtStartDate.Text).AddHours(temp[2] == "PM" ? SafeConvert.ToInt32(temp[0]) + 12 : SafeConvert.ToInt32(temp[0]))                     .AddMinutes(SafeConvert.ToInt32(temp[1]));                   temp = txtEndTime.Value.Split(new char[] { ' ', ':' });                 DateTime endDate = SafeConvert.ToDateTime(txtEndDate.Text).AddHours(temp[2] == "PM" ? SafeConvert.ToInt32(temp[0]) + 12 : SafeConvert.ToInt32(temp[0]))                     .AddMinutes(SafeConvert.ToInt32(temp[1]));                   EmployeeAbsent empAbsent = new EmployeeAbsent();                 empAbsent.UserName = MyUser.UserName;                 empAbsent.EntryDate = DateTime.Now;                 empAbsent.Emlopyee_Id = ddlRollNo.Text;                 empAbsent.Rank_Id = SafeConvert.ToByte(ddlRank.SelectedValue);                 empAbsent.StartDate = startDate;                 empAbsent.EndDate = endDate;                 empAbsent.Durtion = txtDurtion.Text;                 _service.InsertEmployeeAbsent(empAbsent);                 _queryStatus = empAbsent.Id > 0;               }             catch (Exception ex) { HandException(ex); }               Redirect("EmployeeAbsentForm.aspx");         }           protected void btnCancel_Click(object sender, EventArgs e)         {             Response.Redirect("EmployeeAbsentForm.aspx");         }           protected void txtStartDate_TextChanged(object sender, EventArgs e)         {             if (!string.IsNullOrEmpty(txtStartDate.Text) && !string.IsNullOrEmpty(txtstartTime.Value) &&                 !string.IsNullOrEmpty(txtEndDate.Text) && !string.IsNullOrEmpty(txtEndTime.Value))             {                   string[] temp = txtstartTime.Value.Split(new char[] { ' ', ':' });                 DateTime startDate = SafeConvert.ToDateTime(txtStartDate.Text).AddHours(temp[2] == "PM" ? SafeConvert.ToInt32(temp[0]) + 12 : SafeConvert.ToInt32(temp[0]))                     .AddMinutes(SafeConvert.ToInt32(temp[1]));                   temp = txtEndTime.Value.Split(new char[] { ' ', ':' });                 DateTime endDate = SafeConvert.ToDateTime(txtEndDate.Text).AddHours(temp[2] == "PM" ? SafeConvert.ToInt32(temp[0]) + 12 : SafeConvert.ToInt32(temp[0]))                     .AddMinutes(SafeConvert.ToInt32(temp[1]));                   txtDurtion.Text = (endDate - startDate).ToString();               }         }     } }

<%@ Page Title="" Language="C#" MasterPageFile="Site.Master" AutoEventWireup="true"     CodeBehind="EmployeeAbsentForm.aspx.cs" Inherits="CTP.HRMS.WebApp.Forms.EmployeeAbsentForm" %>        
         
<%=Page.Header.Title%>
       
                               
                 
                                              Roll No                                           
                                                                      
                                              Rank                                           
                                                                       
                     
  
                 
                 
                                              Start Date:                                          
                                               
                                              Start Time:                                          
 						 						 					
                     
                 
                                              End Date:                                          
                                                 
                                              End Time:                                          
 						 						 					
                     
  
                 
                 
                                              Durtion: