Last Name/ First Name Reversal?

I know my button is all over the place but in short:

Listbox contains "Lastname, Firstname" and I wan to flip it to "Firstname Lastname"

Using a string.split I can find the comma and remove it but getting sub strings for the rest of the item and exchanging them is beyond me. here's what I have:

Private Sub Button7_Click(sender As System.Object, e As System.EventArgs) Handles Button7.Click
Dim firstname, lastname As Object
For Each Itm As String In ListBox1.Items

[code]....