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 ObjectDataSource 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="CustomersList" DataSourceID="CustomerDataSource"
runat="server">
    <ItemTemplate>
        Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
runat="server"/>
    </ItemTemplate>
</asp:DataList>
<asp:ObjectDataSource ID="CustomerDataSource" SelectMethod="GetCustomers"
TypeName="Customers" runat="server" />

public class Customers
{
    public List<Customer> GetCustomers()
    {
            Customer test = new Customer();
            test.Name = "Uakari Mabuto";
            List<Customer> list = 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

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"  wrote in message 
news:%23W9Cpc$4HHA.6024@TK2MSFTNGP05.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 ObjectDataSource 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="CustomersList" DataSourceID="CustomerDataSource"
> runat="server">
>    <ItemTemplate>
>        Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
> runat="server"/>
>    </ItemTemplate>
> </asp:DataList>
> <asp:ObjectDataSource ID="CustomerDataSource" SelectMethod="GetCustomers"
> TypeName="Customers" runat="server" />
>
> public class Customers
> {
>    public List<Customer> GetCustomers()
>    {
>            Customer test = new Customer();
>            test.Name = "Uakari Mabuto";
>            List<Customer> list = 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
>
>
> 

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.DataBind().

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 ObjectDataSource 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="CustomersList" DataSourceID="CustomerDataSource"
> runat="server">
>     <ItemTemplate>
>         Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
> runat="server"/>
>     </ItemTemplate>
> </asp:DataList>
> <asp:ObjectDataSource ID="CustomerDataSource" SelectMethod="GetCustomers"
> TypeName="Customers" runat="server" />
> 
> public class Customers
> {
>     public List<Customer> GetCustomers()
>     {
>             Customer test = new Customer();
>             test.Name = "Uakari Mabuto";
>             List<Customer> list = 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
> 
> 
> 

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 ObjectDataSource (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)" <NoSpamMgbworld@comcast.netNoSpamM> wrote in 
message news:O0sJb0$4HHA.5164@TK2MSFTNGP05.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"  wrote in message 
> news:%23W9Cpc$4HHA.6024@TK2MSFTNGP05.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 ObjectDataSource 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="CustomersList" DataSourceID="CustomerDataSource"
>> runat="server">
>>    <ItemTemplate>
>>        Name: <asp:Label id="lblName" Text='<%# Eval("Name") %>'
>> runat="server"/>
>>    </ItemTemplate>
>> </asp:DataList>
>> <asp:ObjectDataSource ID="CustomerDataSource" SelectMethod="GetCustomers"
>> TypeName="Customers" runat="server" />
>>
>> public class Customers
>> {
>>    public List<Customer> GetCustomers()
>>    {
>>            Customer test = new Customer();
>>            test.Name = "Uakari Mabuto";
>>            List<Customer> list = 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
>>
>>
>>
>
>