private void BindProductList()
    {
        DataTable dtProductList = new DataTable();

        gvProductList.DataSource = pr.GetProductDetails();
        gvProductList.DataBind();
        DataTable dtBuyerProdList = buyerObj.BuyerProductList(Session["BuyerId"].ToString());

        if (dtBuyerProdList.Rows.Count > 0)
        {
            foreach (DataRow dr in dtBuyerProdList.Rows)
            {
                for (int count = 0; count < gvProductList.Rows.Count; count++)
                {
                    if (gvProductList.DataKeys[count].Value.ToString().Trim() == dr["ProductID"].ToString())
                    {
                        (gvProductList.Rows[count].Cells[0].FindControl("cbitem") as CheckBox).Checked = true;
                    }
                }
            }
        }
    }