form controls :
button
listbox

Code:

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        ListBox1.Items.Add("one")
        ListBox1.Items.Add("two")
        ListBox1.Items.Add("abc")
        ListBox1.Sorted = True
        For I = 0 To ListBox1.Items.Count - 1
            MsgBox(ListBox1.Items(I).ToString)
        Next
    End Sub
End Class


get selected list string item :

Code:

dim str as string = ""
str = ListBox1.SelectedItem