Has a SelectedValue which is invalid because it does not exist

Question

User774350475 posted

On my page, I have ObjectDataSource and ListView. In Oninit method, I am setting selected value of Listbox.

In above scenario, it throws error if I set SelectedValue property of ListBox and if that item does not exist in ListBox collection.

"has a SelectedValue which is invalid because it does not exist "

I want to suppress this error if that item to be have selected does not exist in collection.

I am thinking to hook DataBinding or Selected event of ObjectDataSource and suppress error in that event. Could you please give example of those events in this context?

--
Thanks,
Mahesh
 

Answer 1

User1564875471 posted

 Instead of using the SelectedValue ,

        Dim li As ListItem = DropDownlist1.Items.FindByValue("Value")
        If li IsNot Nothing Then
            li.Selected = True
        End If

 

Answer 2

User774350475 posted

When ListBox is databound using ObjectDataSource, I think ListBox's Items collection would be null.

Answer 3

User848370396 posted

when you wnats to suppress error, then keep that logic in try catch block and leave without writing anything in catch block.

try

{

     your statements

}

catch(Exception e)

{

}

Answer 4

User1564875471 posted

When ListBox is databound using ObjectDataSource, I think ListBox's Items collection would be null

No it shouldn't be null, you need to to access the list \box in Page_PreRender and not page _load , 

so the mentioned code in my previous post must be used in Page_PreRender 

 

As mentioned by the other member , you can use try /catch to handle that error,  But you sdhouldn't rely on try/catch , because it will slows your application , instead you need to check if the value exists before its get selected .