asp.net更新不起作用

Question

I try to do a update in a formview but it doesn't work. I add a breakpoint at the begin of the update methode, and he goes perfectly trough the whole methode. But a classmate told me that at the end of the methode (after "return i") he has to go to the BO.orders.cs, and he doesn't do that. I don't get any errors. Is there somebody who can help me? (Sorry for my bad english)

This is my update methode and GetConnectionString

 public static string GetConnectionString()
    {
        return ConfigurationManager.ConnectionStrings
          ["BookstoreConnectionString"].ConnectionString;
    }

public static int UpdateOrder(Order order)
    {
        SqlConnection conn = new SqlConnection(GetConnectionString());

        string sql = "UPDATE tblOrders " +
          "SET Name = @name, Address = @address, " +
          "City = @city, Pc = @pc, Date = @date, Book_id = @book_id, Count = @count, Amount = @amount, " +
          "Delivered = @delivered, Ddate = @ddate, Paid = @paid, Pdate = @pdate " +
          " WHERE Id = @Id";

        SqlCommand cmd = new SqlCommand(sql, conn);

        cmd.Parameters.AddWithValue("@id", order.OrderId);
        cmd.Parameters.AddWithValue("@name", order.Name);
        cmd.Parameters.AddWithValue("@address", order.Address);
        cmd.Parameters.AddWithValue("@city", order.City);
        cmd.Parameters.AddWithValue("@pc", order.Pc);
        cmd.Parameters.AddWithValue("@date", order.Date);
        cmd.Parameters.AddWithValue("@book_id", order.Bookid);
        cmd.Parameters.AddWithValue("@count", order.Count);
        cmd.Parameters.AddWithValue("@amount", order.Amount);
        cmd.Parameters.AddWithValue("@delivered", order.Delivered);
        cmd.Parameters.AddWithValue("@paid", order.Paid);
        cmd.Parameters.AddWithValue("@ddate", order.Ddate);
        cmd.Parameters.AddWithValue("@pdate", order.Pdate);


        conn.Open();
        int i = cmd.ExecuteNonQuery();
        conn.Close();

        return i;
    }

And this is my objectdatasource of my formview

<asp:ObjectDataSource ID="dtsDetail" runat="server" DataObjectTypeName="BO.Order" DeleteMethod="DeleteOrder" InsertMethod="InsertOrder" OldValuesParameterFormatString="original_{0}" SelectMethod="GetOrdersByOrderId" TypeName="DAL.OrdersDAL" UpdateMethod="UpdateOrder">
    <UpdateParameters>
        <asp:Parameter Name="Date" Type="DateTime" />
        <asp:Parameter Name="Amount" Type="Decimal" />
    </UpdateParameters>
    <SelectParameters>
        <asp:ControlParameter ControlID="gv" Name="ID" PropertyName="SelectedValue" Type="Int32" />
    </SelectParameters>
</asp:ObjectDataSource>

Thanks for helping

Answer 1

If the value of "i" is 0 (as mentioned in the comment) after you've called ExecuteNonQuery(), that means 0 rows were updated after executing your sql query.

Basically, your update statement ( string sql = "UPDATE tblOrders " ...) is looking for a row that has an id of whatever the value of order.OrderID is (... " WHERE Id = @Id"; cmd.Parameters.AddWithValue("@id", order.OrderId); ) and it cannot find a matching row, so it doesn't update anything. So, to get the update working, you will need to provide an id that exists.