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KenDickinsonFlag for United States of America

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How do I bind an array to a listbox?

Greetings Experts...

Disclaimer: Newbie

I've been playing around with writing my own classes and have actually been fairly successful. That being said. I'm trying to use an array as a property in a class. I don't know how to bind the array to a listbox, I don't even know if I declared the array correctly.

Here's the code in the class

    Dim lweekstr As Array = Array.CreateInstance(GetType(Object), 53)
    Public Property weekstr() As Array
        Get
            Return lweekstr
        End Get
        Set(ByVal Value As Array)
            lweekstr = Value
        End Set
    End Property

Here's the code in the class that instantiates the above:

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim f As New ClassLibrary1.CalendarClass
        f.Year = 2004
        f.test() 'this method populates the array
        Me.ListBox1.DataSource = f.weekstr
        '---- this code tests to see if there is something in the array(there is)
        Dim c As Integer
        For c = 1 To 10
            MsgBox(f.weekstr(c))
        Next
    End Sub

Thanks in advance for your help
 
Avatar of Bob Learned
Bob Learned
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If you are trying to store an Integer into an Object array, there is a performance hit from converting a value type (Integer) into an object type to store in the array (this is called boxing).  Use a type-specific declaration instead:

Dim lWeekStr As Integer()

Bob
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bramsquad
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Avatar of iboutchkine
iboutchkine

To bind lb to array
  ListBox1.DataSource = (arr)


To ppulate array from lb

ListBox1.Items.CopyTo(arr, 0)



or all together - populate array from lb and back to array

 Dim arr(ListBox1.Items.Count - 1)

        ListBox1.Items.CopyTo(arr, 0)
        ListBox1.Items.Clear()
        MessageBox.Show(Join(arr, ";"))
        ListBox1.Items.AddRange(arr)