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asp.net - selected listbox items into array

Posted on 2010-11-16
4
845 Views
Last Modified: 2012-05-10
Hello,

I have a ListBox control that is being populated in code (from a SQL query).

How do I set the selected items to an ArrayList?


Protected Sub btnGo_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnGo.Click

        Dim arrBrand As ArrayList

        For Each item As ListItem In lstBxBrand.Items
            If item.Selected = True Then
                arrBrand.Add(item.Text)
            End If
        Next

End Sub


This is giving me a "Object reference not set to an instance of an object", on:

                arrBrand.Add(item.Text)



Thank you.

0
Comment
Question by:Rick
4 Comments
 
LVL 5

Accepted Solution

by:
Vipul Patel earned 500 total points
ID: 34147171
You have missed to initialize the array object.

The correct code would be like;
Protected Sub btnGo_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnGo.Click

        Dim arrBrand As ArrayList = New ArrayList()

        For Each item As ListItem In lstBxBrand.Items
            If item.Selected = True Then
                arrBrand.Add(item.Text)
            End If
        Next

End Sub
0
 
LVL 6

Expert Comment

by:ajb2222
ID: 34147193
You have declared array brand but havenot set it to an object

add this line after the dim statement

arrBrand = new ArrayList
0
 
LVL 13

Author Closing Comment

by:Rick
ID: 34147212
Thank you.
0
 
LVL 13

Expert Comment

by:devlab2012
ID: 34147215
Change the following line:

Dim arrBrand As ArrayList

to

Dim arrBrand As New ArrayList

0

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