Dropdownlist doesn't get recognised without selected items

Hello,

I've been watching this list for some time to improve mijn
.net skills 
and now i've encountered a problem where i can't find any
information about.

I have several dropdownlists and want to check if the
previous list has 
selected items or not using followin code

if ( dropdown1.SelectedIndex <= 0)

But i get a System.NullReferenceException

On pageload i fill the dropdowns, i even set the
selectedIndex to the 
first item. The code i use is in the second dropdown
autoPostback 
function. But it still gives me a nullreferenceexception.

Could some help me? Thank you

-- 
David Duymelinck
________________
davidicreate.be


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How about (C#):

if ( dropdown1.SelectedIndex == null ||
dropdown1.SelectedIndex < 0)

Remember that it's zero-based
(http://msdn2.microsoft.com/en-us/library/
system.web.ui.webcontrols.drop
downlist.selectedindex.aspx) so 0 is a valid selection.


_____
Peter Smith

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hi,
did u check that the dropdown1 object is initialized?
Regards
Kannan.P

On Oct 12, 2:35 pm, David Duymelinck <da...icreate.be> wrote:
> Hello,
>
> I've been watching this list for some time to improve
mijn .net skills
> and now i've encountered a problem where i can't find
any information about.
>
> I have several dropdownlists and want to check if the
previous list has
> selected items or not using followin code
>
> if ( dropdown1.SelectedIndex <= 0)
>
> But i get a System.NullReferenceException
>
> On pageload i fill the dropdowns, i even set the
selectedIndex to the
> first item. The code i use is in the second dropdown
autoPostback
> function. But it still gives me a
nullreferenceexception.
>
> Could some help me? Thank you
>
> --
> David Duymelinck
> ________________
> da...icreate.be


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It would be better if you send the block of code where u get
the null
reference exception and also the code where you fill up the
combo box.
There are ways around to resolve null reference exception
and
gracefully handle it but you should not get that exception
at first
place looking to your description of problem.


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