public bool update(product_detailsbll u)
        {
            //Create a boolean variable and set its value to false and return it
            bool issucess = false;
            //MEthod to connect Database
            connclass     c    = new connclass();
            SqlConnection conn = new SqlConnection(c.connection);

            try
            {
                //SQL Query to insert Data in DAtabase
                string query = "UPDATE tbl_productdetails set product_id=@product_id,product_name=@product_name,price=@price,quantity=@quantity,discount=@discount,total=@total,purchase_price=@purchase_price,inv_no=@inv_no,type=@type,added_by=@added_by,added_date=@added_date,code=@code WHERE id=@id";
                //For Executing Command
                SqlCommand cmd = new SqlCommand(query, conn);
                //Passing Values to the Variables
                cmd.Parameters.AddWithValue("@id", u.id);
                cmd.Parameters.AddWithValue("@product_id", u.product_id);
                cmd.Parameters.AddWithValue("@product_name", u.product_name);
                cmd.Parameters.AddWithValue("@price", u.price);
                cmd.Parameters.AddWithValue("@quantity", u.quantity);
                cmd.Parameters.AddWithValue("@discount", u.discount);
                cmd.Parameters.AddWithValue("@total", u.total);
                cmd.Parameters.AddWithValue("@purchase_price", u.purchase_price);
                cmd.Parameters.AddWithValue("@inv_no", u.inv_no);
                cmd.Parameters.AddWithValue("@type", u.type);
                cmd.Parameters.AddWithValue("@added_by", u.added_by);
                cmd.Parameters.AddWithValue("@added_date", u.added_date);
                cmd.Parameters.AddWithValue("@code", u.code);
                //Database Connection Open
                conn.Open();
                //To execute non query
                int rows = cmd.ExecuteNonQuery();
                //If the query is executed Successfully then the value to rows will be greater than 0 else it will be less than 0
                if (rows > 0)
                {
                    //Query Sucessfull
                    issucess = true;
                }
                else
                {
                    //Query Failed
                    issucess = false;
                }
            }
            catch (Exception ex)
            {
                //Throw Message if any error occurs
                MessageBox.Show(ex.Message);
            }
            finally
            {
                //Closing Connection
                conn.Close();
            }

            return(issucess);
        }
        public bool delete(product_detailsbll u)
        {
            //Create a boolean variable and set its value to false and return it
            bool issucess = false;
            //MEthod to connect Database
            connclass     c    = new connclass();
            SqlConnection conn = new SqlConnection(c.connection);

            try
            {
                //SQL Query to delete Data in DAtabase
                string query = "DELETE FROM tbl_productdetails WHERE id=@id";
                //For Executing Command
                SqlCommand cmd = new SqlCommand(query, conn);
                //Passing Values to the Variables
                cmd.Parameters.AddWithValue("@id", u.id);
                //Database Connection Open
                conn.Open();
                //To execute non query
                int row = cmd.ExecuteNonQuery();
                //If the query is executed Successfully then the value to rows will be greater than 0 else it will be less than 0
                if (row > 0)
                {
                    //Query Sucessfull
                    issucess = true;
                }
                else
                {
                    //Query Failed
                    issucess = false;
                }
            }

            catch (Exception ex)
            {
                //Throw Message if any error occurs
                MessageBox.Show(ex.Message);
            }
            finally
            {
                //Closing Connection
                conn.Close();
            }

            return(issucess);
        }