private void Search() { SqlInt32 CustomerID = SqlInt32.Null; SqlString MobileNo = SqlString.Null; SqlInt32 ProductID = SqlInt32.Null; if (ddlCustomerID.SelectedIndex > 0) { CustomerID = Convert.ToInt32(ddlCustomerID.SelectedValue); } if (txtMobileSerch.Text.Trim() != "") { MobileNo = Convert.ToString(txtMobileSerch.Text.Trim()); } if (ddlProductID.SelectedIndex > 0) { ProductID = Convert.ToInt32(ddlProductID.SelectedValue); } CustomerBAL balCustomer = new CustomerBAL(); DataTable dtCustomer = balCustomer.CustomerSelectSearch(CustomerID, MobileNo, ProductID); if (dtCustomer != null && dtCustomer.Rows.Count > 0) { gvCustomer.DataSource = dtCustomer; gvCustomer.DataBind(); } else { gvCustomer.DataSource = null; gvCustomer.DataBind(); } }