this field one of the Gridview field and i need it but my Gridview have paging and data from another page have problem with this code.

Thank you I don't know this,,,, but my code have loop and must check All of Cell about up code What can I do? my complete code is:
protected void lnkAddoptional_Click(object sender, EventArgs e)
{
LinkButton lnkbtn = sender as LinkButton;
//getting particular row linkbutton
GridViewRow gvrow = lnkbtn.NamingContainer as GridViewRow;
// //getting userid of particular row
string eno = GridViewOptional.DataKeys[gvrow.RowIndex].Value.ToString();
// // string Coursename = gvrow.Cells[0].Text;
DataTable Temp = new DataTable();
Temp.Clear();
Temp = Session["Select_optional"] as DataTable;
for (int i = 0; i <= Temp.Rows.Count - 1; i++)
{

DataRow dr;
if (((System.Web.UI.WebControls.HiddenField)(GridViewOptional.Rows[i].Cells[1].FindControl("HiddenField1"))).Value.ToString() == Convert.ToString(eno))
{
string ProductId = ((HiddenField)GridViewOptional.Rows[i].Cells[0].FindControl("HiddenField1")).Value;
Label Cost = (Label)GridViewOptional.Rows[i].Cells[1].FindControl("LblCost");
Label lbldscribe = (Label)GridViewOptional.Rows[i].Cells[2].FindControl("Labeldiscribe");
DataRow row = Second_Sel.NewRow();

row[0] = lbldscribe.Text;
row[1] = Cost.Text;
row[2] = ProductId;
Second_Sel.Rows.Add(row);
dr = Temp.Rows[i];
Temp.Rows[i].Delete();
}
}
a mean I have linkBotton in first Gridview and I want to when click on linkbotton from first Gridview data transfer to second Gridview and delete from first gridview and I have not any database justlike sql and I just work with datatable and I have to check all of field but some field in another page of gridview and have a Error that i discribe in my question what canI do?

I Share my code please help me

Thank you I don't know this,,,, but my code have loop and must check All of Cell about up code What can I do? my complete code is: protected void lnkAddoptional_Click(object sender, EventArgs e) { LinkButton lnkbtn = sender as LinkButton; //getting particular row linkbutton GridViewRow gvrow = lnkbtn.NamingContainer as GridViewRow; // //getting userid of particular row string eno = GridViewOptional.DataKeys[gvrow.RowIndex].Value.ToString(); // // string Coursename = gvrow.Cells[0].Text; DataTable Temp = new DataTable(); Temp.Clear(); Temp = Session["Select_optional"] as DataTable; for (int i = 0; i <= Temp.Rows.Count - 1; i++) { DataRow dr; if (((System.Web.UI.WebControls.HiddenField)(GridViewOptional.Rows[i].Cells[1].FindControl("HiddenField1"))).Value.ToString() == Convert.ToString(eno)) { string ProductId = ((HiddenField)GridViewOptional.Rows[i].Cells[0].FindControl("HiddenField1")).Value; Label Cost = (Label)GridViewOptional.Rows[i].Cells[1].FindControl("LblCost"); Label lbldscribe = (Label)GridViewOptional.Rows[i].Cells[2].FindControl("Labeldiscribe"); DataRow row = Second_Sel.NewRow(); row[0] = lbldscribe.Text; row[1] = Cost.Text; row[2] = ProductId; Second_Sel.Rows.Add(row); dr = Temp.Rows[i]; Temp.Rows[i].Delete(); } } a mean I have linkBotton in first Gridview and I want to when click on linkbotton from first Gridview data transfer to second Gridview and delete from first gridview and I have not any database justlike sql and I just work with datatable and I have to check all of field but some field in another page of gridview and have a Error that i discribe in my question what canI do?