How to save or load the dock state of WinForms Docking Manager in XML format?

private void Form1_Load(object sender, EventArgs e)
{
    // load
    AppStateSerializer serializer = new AppStateSerializer(SerializeMode.XMLFile, "myfile");
    m_dockingManagerForDisplay.LoadDockState(serializer);
}
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
    //save
    AppStateSerializer serializer = new AppStateSerializer(SerializeMode.XMLFile, "myfile");
    this.m_dockingManagerForDisplay.SaveDockState(serializer);
    serializer.PersistNow();
}

Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
    'load
    Dim serializer As New AppStateSerializer(SerializeMode.XMLFile, "myfile")
    m_dockingManagerForDisplay.LoadDockState(serializer)
End Sub
Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As FormClosingEventArgs) Handles MyBase.FormClosing
    'save
     Dim serializer As New AppStateSerializer(SerializeMode.XMLFile, "myfile")
     Me.m_dockingManagerForDisplay.SaveDockState(serializer)
     serializer.PersistNow()
End Sub