Delete with ObjectDataSourc e does not work

[Jürgen Bayer]

Hi,

I just tried out the ObjectDataSourc e of ASP.NET 2.0. A simple application
works with a GridView bound to an ObjectDataSourc e. The ObjectDataSourc e is
set to a (factory) class (PersonFactory) with static methods (Select,
Update, Delete, see below). The factory methods work with instances of a
simple class (Person, see below). Select and Update works, but the Person
object passed to the Delete method is always empty (Id == 0; FirstName ==
null, LastName == 0). I tried to use factory methods with separate
parameters, but the (Person)Id parameter passed to the Delete method is also
0.

Anyone who knows what's wrong?

Juergen

The Person class
************
public class Person
{
private int id;
public int Id
{
get { return this.id; }
set { this.id = value; }
}

private string firstName;
public string FirstName
{
get { return this.firstName; }
set { this.firstName = value; }
}

private string lastName;
public string LastName
{
get { return this.lastName; }
set { this.lastName = value; }
}
}

The PersonFactory class (simplified)
*************** ************
public class PersonFactory
{
public static List<Person> Select()
{
List<Person> persons = new List<Person>();

// "Read" persons
Person p = new Person();
p.Id = 1001;
p.FirstName = "Zaphod";
p.LastName = "Beeblebrox ";
persons.Add(p);

p = new Person();
p.Id = 1002;
p.FirstName = "Ford";
p.LastName = "Prefect";
persons.Add(p);

return persons;
}

public static void Update(Person p)
{
// Update person
// ...
}

public static void Delete(Person p)
{
// Delete Person
// But: p is an empty object (p.Id == 0) !???
}
}

The ObjectDataSourc e and the GridView on the Web form
*************** *************** ***************
<asp:ObjectData Source ID="personDataS ource" runat="server"
SelectMethod="S elect"
TypeName="Perso nFactory" DeleteMethod="D elete" InsertMethod="I nsert"
UpdateMethod="U pdate"
DataObjectTypeN ame="Person">
</asp:ObjectDataS ource>

<asp:GridView ID="personGridV iew" runat="server" AutoGenerateCol umns="False"
DataSourceID="p ersonDataSource "
BackColor="Whit e" BorderColor="#C CCCCC" BorderStyle="No ne"
BorderWidth="1p x" CellPadding="4"
ForeColor="Blac k" GridLines="Hori zontal">
<Columns>
<asp:CommandFie ld ShowDeleteButto n="True" ShowEditButton= "True" />
<asp:BoundFie ld DataField="Id" HeaderText="Id" SortExpression= "Id" />
<asp:BoundFie ld DataField="Firs tName" HeaderText="Fir stName"
SortExpression= "FirstName" />
<asp:BoundFie ld DataField="Last Name" HeaderText="Las tName"
SortExpression= "LastName" />
</Columns>
<FooterStyle BackColor="#CCC C99" ForeColor="Blac k" />
<SelectedRowSty le BackColor="#CC3 333" Font-Bold="True" ForeColor="Whit e"
/>
<PagerStyle BackColor="Whit e" ForeColor="Blac k" HorizontalAlign ="Right"
/>
<HeaderStyle BackColor="#333 333" Font-Bold="True" ForeColor="Whit e" />
</asp:GridView>

[Jürgen Bayer]

I found the answer myself: I have to set the DataKeyNames propery to the
name of the Id property.