Private Sub PictureBoxX_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs)
 
     Dim g As String
     g = ReadValue("SYSTEM\ControlSet001\Services\Themes", "Start")
 
     Select Case g
          Case "4"
               DirectCast(sender, Button).Image = Me.ImageList1.Images(0)
          Case "2"
               DirectCast(sender, Button).Image = Me.ImageList1.Images(1)
     End Select
 
End Sub

AddHandler PictureBox1.Click, AddressOf PictureBoxX_Click
AddHandler PictureBox2.Click, AddressOf PictureBoxX_Click
AddHandler PictureBox3.Click, AddressOf PictureBoxX_Click
AddHandler PictureBox4.Click, AddressOf PictureBoxX_Click
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