请各位朋友帮我写一下注释，就写在程序边上

<P>Dim m_ptsDemo As MapObjects2.Points
Dim m_nNum As Integer
Dim m_Evt As GeoEvent
Dim m_bIsMove As Boolean</P>
<P>Private Sub Form_Load()
  Dim Layer As MapLayer
  Dim dc As New DataConnection
  dc.Database = App.Path
  If Not dc.Connect Then
    MsgBox "在指定的文件夹下没找到图层数据文件，退出GIS！"
    Unload Me
    Exit Sub
  End If
  Set Layer = New MapLayer
  Set Layer.GeoDataset = dc.FindGeoDataset("图层 1_l")
  Layer.Name = "图层 1"
  Layer.Symbol.Color = moRed
  Layer.Symbol.Size = 2
  Map1.Layers.Add Layer
  
  Map1.Refresh
  
  Map1.TrackingLayer.SymbolCount = 2
  With Map1.TrackingLayer.Symbol(0)
    .SymbolType = moPointSymbol
    .Color = moBlue
    .Style = 0
    .Size = 8
  End With
  
  With Map1.TrackingLayer.Symbol(1)
    .SymbolType = moLineSymbol
    .Color = moBlue
    .Style = 0
    .Size = 5
  End With
  
  m_bIsMove = True
  Num = 0
End Sub</P>
<P>Private Sub Map1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
  Dim p1 As MapObjects2.Point
  Dim theTol
  Dim line
  
  theTol = Map1.ToMapDistance(300)
  Set Layer1 = Map1.Layers(0)
  Set p1 = Map1.ToMapPoint(X, Y)
  Set recs1 = Layer1.SearchByDistance(p1, theTol, "")
  Timer1.Interval = 0
      
  If Button = 2 Then
    Timer1.Interval = 0
    Map1.TrackingLayer.ClearEvents
    Exit Sub
  Else
    Map1.TrackingLayer.ClearEvents
    m_nNum = 0
  End If
  
  If Not recs1.EOF And Map1.Layers(0).Visible = True Then
    Set line = recs1("Shape").Value
    Set m_ptsDemo = New MapObjects2.Points
    
    For Each pt In line.Parts(0)
        m_ptsDemo.Add pt
    Next pt
    
    p1.X = m_ptsDemo.Item(0).X
    p1.Y = m_ptsDemo.Item(0).Y
    Set m_Evnt = Map1.TrackingLayer.AddEvent(p1, 0)
    m_bIsMove = True
    Timer1.Interval = 500
  End If
End Sub</P>
<P>Private Sub Timer1_Timer()
  Dim count As Integer
  Dim X, Y
  
  If m_bIsMove And Map1.TrackingLayer.EventCount > 0 Then
    count = m_nNum
    If count >= m_ptsDemo.count Then
        Timer1.Interval = 0
        MsgBox "END"
        Exit Sub
    End If
    
    Set m_Evnt = Map1.TrackingLayer.Event(0)
    m_nNum = m_nNum + 1
    X = m_ptsDemo.Item(count).X
    Y = m_ptsDemo.Item(count).Y
    m_Evnt.MoveTo X, Y
  End If
End Sub
</P>

<P>这不是MO自带的例子吗？看看运行情况再理解程序吧！</P>