see this datagrid problem

[a developer]

my table has total 3 columns like emp_id(primay key),emp_name emp_address
i m populating my datagrid at run time successfully .
now i add functionality of hotmail model(checkboxex) in it successfully
but for this i did enhanced simple datagrid's functionality and
add one template column and placed label on it (so that i could do deletion
of records
selcted by user by checkboxes when a user clik on "Delete" button .
in label i took emp_id as field

NOW MY PROBLEM IS

"how can i hide my emp_id column at run time ..i need(want)
to see only 3 columns at run time(checkbox templte column
,emp_name,emp_address)
i tried DataGrid1.Columns[2].Visible=false(2 is number of emp_id)
but it did give following error..


Exception Details: System.ArgumentOutOfRangeException: Index was out of
range.
Must be non-negative and less than the size of the collection. Parameter
name: index
DataGrid1.Columns[2].Visible=false;<----------------(error in this
line)
if i dont choose emp_id in SQL Query then a new error comes in my template
column.."Unknown Column name"
plz sugesst me
ACTUAL CODE IS :-
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using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;

namespace fifthpro
{
/// <summary>
/// Summary description for WebForm1.
/// </summary>
public class WebForm1 : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Button btnAdd;
protected System.Web.UI.WebControls.DataGrid DataGrid1;
public SqlConnection objConn;
public const string ConnStr=
"uid=sa;pwd=password;server=NEW103;database=Car_test";

protected System.Web.UI.WebControls.Button Confirm;


private void Page_Load(object sender, System.EventArgs e)
{

// Put user code to initialize the page here
if(!IsPostBack)
{
fnFillGrid();
}


string jsScript = "<script language=JavaScript> "
+" function confirmDelete (frm) {"
+" for (i=0; i<frm.length; i++) {"
+" if (frm.elements.name.indexOf ('DeleteThis') !=-1) {"
+" if(frm.elements.checked) {return confirm ('Are you sure you want
to delete your selection(s)?')}"
+" }}}"
+" function select_deselectAll (chkVal, idVal){"
+" var frm = document.forms[0];"
+" for (i=0; i<frm.length; i++) {"
+" if (idVal.indexOf ('CheckAll') != -1) {"
+" if(chkVal == true) { frm.elements.checked = true;"
+" } else {"
+" frm.elements.checked = false;"
+" } } else if (idVal.indexOf('DeleteThis') != -1) {"
+" if(frm.elements.checked == false) {"
+" frm.elements[1].checked = false;"
+" } }}}</script>";

RegisterClientScriptBlock("clientScript", jsScript);
WebControl button = (WebControl) Page.FindControl ("Confirm");
button.Attributes.Add ("onclick", "return confirmDelete (this.form);");
}


#region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}

/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.btnAdd.Click += new System.EventHandler(this.btnAdd_Click);
this.DataGrid1.PageIndexChanged += new
System.Web.UI.WebControls.DataGridPageChangedEventHandler(this.DataGrid1_PageIndexChanged);
this.Load += new System.EventHandler(this.Page_Load);

}
#endregion


#region "UI Layer"

private void btnAdd_Click(object sender, System.EventArgs e)
{
string strCheckStatus="Add";
Session["strCheckStatus"]=strCheckStatus;
Response.Redirect("SetAlert.aspx");
}

private void fnFillGrid()
{
DataSet ds=new DataSet();
ds=fnFillControls();
DataGrid1.DataSource=ds;
DataGrid1.Columns[2].Visible=false;

DataGrid1.DataBind();

foreach (DataGridItem dgi in DataGrid1.Items)
{
dgi.Attributes.Add("onmouseover", "this.style.backgroundColor='#ffcc99'");
dgi.Attributes.Add("onmouseout",
"this.style.backgroundColor='Peachpuff'");
}
}

private void DataGrid1_PageIndexChanged(object source,
System.Web.UI.WebControls.DataGridPageChangedEventArgs e)
{
DataGrid1.CurrentPageIndex=e.NewPageIndex;
fnFillGrid();
}
#endregion

#region "Business Logic"

public DataSet fnFillControls()
{
//string SqlStatement="select
AlertID,Date,Site,ComparesWith,CountryID,CityId,CarType,Figure,Variance,Compare,EmailId,CcEmailId,BCcEmailId,'<a
target=display href=SetAlert.aspx?ALERTID'+'='+convert(varchar(10),ALERTID)+'

'+convert(varchar(10),SITE)+'</a>' from SetAlert";

string SqlStatement="select Date,Site,CountryId As 'Country',CityId as
'City',CarType,"
+" (figure + ',' + variance+ ',' + compare) as '
Values[Figure,Variance,Compare]',EmailId as 'Emails',"
+" '<a target=display
href=SetAlert.aspx?ALERTID'+'='+convert(varchar(10),ALERTID)+'"
+" >'+'<b>DETAILS</b>'+'</a>' AS [Show Detail],AlertID from SetAlert";
return fnGetDataSet(SqlStatement);
}

public void DeleteAlerts (Object sender, EventArgs e)
{
string dgIDs = "";
bool BxsChkd = false;
foreach (DataGridItem i in DataGrid1.Items)
{
CheckBox deleteChkBxItem = (CheckBox)i.FindControl("DeleteThis");
if (deleteChkBxItem.Checked)
{
BxsChkd = true;
dgIDs += Convert.ToInt32(((Label) i.FindControl
("AlertID")).Text.ToString()) + ",";
}
}
string SqlStatement="delete from SetAlert where AlertID IN (" +
dgIDs.Substring(0,dgIDs.LastIndexOf(",")) + ")";
if (BxsChkd == true)
{
SqlConnection objConn1;
const string
ConnStr1="uid=sa;pwd=password;server=NEW103;database=CAR_TEST";
objConn1=new SqlConnection(ConnStr1);
string SqlStatement1="delete from SetAlert where AlertID IN (" +
dgIDs.Substring(0,dgIDs.LastIndexOf(",")) + ")";
if(objConn1.State==ConnectionState.Closed)
objConn1.Open();
SqlCommand cmd=new SqlCommand(SqlStatement1,objConn1);
cmd.ExecuteNonQuery();
objConn1.Close();
fnFillGrid();
}
}
#endregion

#region "DataLayer"

private SqlConnection fnGetConnection()
{
objConn=new SqlConnection(ConnStr);
return objConn;
}

private string fnConnectString()
{
string ConnectString="uid=sa;pwd=password;server=NEW103;database=Car_test";
return ConnectString;
}

public DataSet fnGetDataSet(string SqlStatement)
{
DataSet MyDataSet=new DataSet();
objConn=new SqlConnection(fnConnectString());
SqlDataAdapter da=new SqlDataAdapter(SqlStatement,objConn);
da.Fill(MyDataSet);
return MyDataSet;
}

public int fnExecuteNonQuery(string SqlStatement)
{
SqlConnection objConn=fnGetConnection();
if (objConn.State==ConnectionState.Closed)
objConn.Open();
SqlCommand cmd=new SqlCommand(SqlStatement,objConn);
int i=cmd.ExecuteNonQuery();
if (objConn.State==ConnectionState.Open)
objConn.Close();
return i;
}

#endregion

}
}
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