hi sir....i have added rowbound event and it worked for me.
protected void gvDetails_RowDataBound(object sender, GridViewRowEventArgs e)
{
DataRowView drv = e.Row.DataItem as DataRowView;
if (e.Row.RowType == DataControlRowType.DataRow)
{
if ((e.Row.RowState & DataControlRowState.Edit) > 0)
{
((TextBox)gvDetails.FooterRow.FindControl("txtfpercentage")).Attributes.Add("readonly", "readonly");
((TextBox)gvDetails.FooterRow.FindControl("txtftrdifference")).Attributes.Add("readonly", "readonly");
//((TextBox)gvDetails.Row.FindControl("txtdifference")).Attributes.Add("readonly", "readonly");
RadioButtonList rbtnl = (RadioButtonList)e.Row.FindControl("rdottstatus");
rbtnl.SelectedValue = drv[4].ToString();
RadioButtonList rbtnl1 = (RadioButtonList)e.Row.FindControl("rdoConfirmation");
rbtnl1.SelectedValue = drv[5].ToString();
}
}
}