Select method of ObjectDataSourc e called twice - second post

[TarTar]

Hello,

I have already posted this problem, but I have not received any response
yet. I will try to describe it again.

We have a list control (e.g. DataList) and an ObjectDataSourc e on an ASP.NET
web page. When we open the page the Select method (here: GetCustomers) is
called twice. Why? It is obvious performance hit as the data needs to be
retrieved twice. How to avoid the duplicated calls?

Below there is complete code for both the ASP.NET page and its code-behind:

<asp:DataList ID="CustomersLi st" DataSourceID="C ustomerDataSour ce"
runat="server">
<ItemTemplate >
Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
runat="server"/>
</ItemTemplate>
</asp:DataList>
<asp:ObjectData Source ID="CustomerDat aSource" SelectMethod="G etCustomers"
TypeName="Custo mers" runat="server" />

public class Customers
{
public List<CustomerGe tCustomers()
{
Customer test = new Customer();
test.Name = "Uakari Mabuto";
List<Customerli st = new List<Customer>( );
list.Add(test);
return list;
}
}
public class Customer
{
private string name;
public string Name
{
get { return name; }
set { name = value; }
}
}
Thanks,
Leszek

[Cowboy \(Gregory A. Beamer\)]

It does not look like you posted the actual code behind for the page here,
or is that an empty file? I see nothing wrong with the class file or the
ASP.NET tagged portion.

--
Gregory A. Beamer
MVP, MCP: +I, SE, SD, DBA

*************** *************** *************** ****
| Think outside the box!
|
*************** *************** *************** ****
"TarTar" <sp*******@love ly.spamwrote in message
news:%2******** ********@TK2MSF TNGP05.phx.gbl. ..

Hello,

I have already posted this problem, but I have not received any response
yet. I will try to describe it again.

We have a list control (e.g. DataList) and an ObjectDataSourc e on an
ASP.NET web page. When we open the page the Select method (here:
GetCustomers) is called twice. Why? It is obvious performance hit as the
data needs to be retrieved twice. How to avoid the duplicated calls?

Below there is complete code for both the ASP.NET page and its
code-behind:

<asp:DataList ID="CustomersLi st" DataSourceID="C ustomerDataSour ce"
runat="server">
<ItemTemplate >
Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
runat="server"/>
</ItemTemplate>
</asp:DataList>
<asp:ObjectData Source ID="CustomerDat aSource" SelectMethod="G etCustomers"
TypeName="Custo mers" runat="server" />

public class Customers
{
public List<CustomerGe tCustomers()
{
Customer test = new Customer();
test.Name = "Uakari Mabuto";
List<Customerli st = new List<Customer>( );
list.Add(test);
return list;
}
}
public class Customer
{
private string name;
public string Name
{
get { return name; }
set { name = value; }
}
}
Thanks,
Leszek

[Steve]

It sounds like the databinding is being called twice. Check your
Page_Load event to see if you're doing something like calling
Page.DataBind() , then DataList1.DataB ind().

You also could have something in the Page_Load that causes it to re-load
the current page??
Steve C.
MCAD,MCSE,MCP+I ,CNE,CNA,CCNA
TarTar wrote:

Hello,

I have already posted this problem, but I have not received any response
yet. I will try to describe it again.

We have a list control (e.g. DataList) and an ObjectDataSourc e on an ASP.NET
web page. When we open the page the Select method (here: GetCustomers) is
called twice. Why? It is obvious performance hit as the data needs to be
retrieved twice. How to avoid the duplicated calls?

Below there is complete code for both the ASP.NET page and its code-behind:

<asp:DataList ID="CustomersLi st" DataSourceID="C ustomerDataSour ce"
runat="server">
<ItemTemplate >
Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
runat="server"/>
</ItemTemplate>
</asp:DataList>
<asp:ObjectData Source ID="CustomerDat aSource" SelectMethod="G etCustomers"
TypeName="Custo mers" runat="server" />

public class Customers
{
public List<CustomerGe tCustomers()
{
Customer test = new Customer();
test.Name = "Uakari Mabuto";
List<Customerli st = new List<Customer>( );
list.Add(test);
return list;
}
}
public class Customer
{
private string name;
public string Name
{
get { return name; }
set { name = value; }
}
}
Thanks,
Leszek

[TarTar]

Thanks Steve and Cowboy for the answers.

I agree - the ASP.NET code and C# code looks fine. There is also no code in
Page_Load. Yet, the GetCustomers() method is called twice when the page is
called first time. It looks like a built-in feature of ObjectDataSourc e (or
the DataList control?).
Whay is that? The code is very rudimentary - no parameters, no code in
Page_Load or any other event handler.

Thanks,
Leszek

"Cowboy (Gregory A. Beamer)" <No************ @comcast.netNoS pamMwrote in
message news:O0******** ******@TK2MSFTN GP05.phx.gbl...

It does not look like you posted the actual code behind for the page here,
or is that an empty file? I see nothing wrong with the class file or the
ASP.NET tagged portion.

--
Gregory A. Beamer
MVP, MCP: +I, SE, SD, DBA

*************** *************** *************** ****
| Think outside the box! |
*************** *************** *************** ****
"TarTar" <sp*******@love ly.spamwrote in message
news:%2******** ********@TK2MSF TNGP05.phx.gbl. ..

>Hello,

I have already posted this problem, but I have not received any response
yet. I will try to describe it again.

We have a list control (e.g. DataList) and an ObjectDataSourc e on an
ASP.NET web page. When we open the page the Select method (here:
GetCustomers ) is called twice. Why? It is obvious performance hit as the
data needs to be retrieved twice. How to avoid the duplicated calls?

Below there is complete code for both the ASP.NET page and its
code-behind:

<asp:DataLis t ID="CustomersLi st" DataSourceID="C ustomerDataSour ce"
runat="server" >
<ItemTemplate >
Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
runat="serve r"/>
</ItemTemplate>
</asp:DataList>
<asp:ObjectDat aSource ID="CustomerDat aSource" SelectMethod="G etCustomers"
TypeName="Cust omers" runat="server" />

public class Customers
{
public List<CustomerGe tCustomers()
{
Customer test = new Customer();
test.Name = "Uakari Mabuto";
List<Customerli st = new List<Customer>( );
list.Add(test);
return list;
}
}
public class Customer
{
private string name;
public string Name
{
get { return name; }
set { name = value; }
}
}
Thanks,
Leszek

[TarTar]

Problem solved - but it is the weirdest quirk of ASP.NET (or Visual Studio
and its built-in web server) I have met so far.
It turned out the cause was not the ObjectDataSourc e or any event handler
but the filename. When I renamed the file from Default.aspx to
Homepage.aspx, calls are not duplicated any more.

Leszek

"TarTar" <sp*******@love ly.spamwrote in message
news:O$******** ******@TK2MSFTN GP04.phx.gbl...

Thanks Steve and Cowboy for the answers.

I agree - the ASP.NET code and C# code looks fine. There is also no code
in Page_Load. Yet, the GetCustomers() method is called twice when the page
is called first time. It looks like a built-in feature of ObjectDataSourc e
(or the DataList control?).
Whay is that? The code is very rudimentary - no parameters, no code in
Page_Load or any other event handler.

Thanks,
Leszek

"Cowboy (Gregory A. Beamer)" <No************ @comcast.netNoS pamMwrote in
message news:O0******** ******@TK2MSFTN GP05.phx.gbl...

>It does not look like you posted the actual code behind for the page
here, or is that an empty file? I see nothing wrong with the class file
or the ASP.NET tagged portion.

--
Gregory A. Beamer
MVP, MCP: +I, SE, SD, DBA

************** *************** *************** *****
| Think outside the box! |
************** *************** *************** *****
"TarTar" <sp*******@love ly.spamwrote in message
news:%2******* *********@TK2MS FTNGP05.phx.gbl ...

>>Hello,

I have already posted this problem, but I have not received any response
yet. I will try to describe it again.

We have a list control (e.g. DataList) and an ObjectDataSourc e on an
ASP.NET web page. When we open the page the Select method (here:
GetCustomer s) is called twice. Why? It is obvious performance hit as the
data needs to be retrieved twice. How to avoid the duplicated calls?

Below there is complete code for both the ASP.NET page and its
code-behind:

<asp:DataLi st ID="CustomersLi st" DataSourceID="C ustomerDataSour ce"
runat="server ">
<ItemTemplate >
Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
runat="server "/>
</ItemTemplate>
</asp:DataList>
<asp:ObjectDa taSource ID="CustomerDat aSource"
SelectMethod= "GetCustome rs"
TypeName="Cus tomers" runat="server" />

public class Customers
{
public List<CustomerGe tCustomers()
{
Customer test = new Customer();
test.Name = "Uakari Mabuto";
List<Customerli st = new List<Customer>( );
list.Add(test);
return list;
}
}
public class Customer
{
private string name;
public string Name
{
get { return name; }
set { name = value; }
}
}
Thanks,
Leszek