徵求高手解答难题…..

<P ><FONT size=3><FONT face="Times New Roman">请GIS开发高手，帮小弟看看这段程序码哪边错误了！图层放大的功能可以使用，却没有办法缩小图层，！感激不尽…..<p></p></FONT></FONT></P>
<P>Private Sub AxMapControl1_OnMouseDown(ByVal sender As System.Object, ByVal a As AxesriMapControl.IMapControlEvents2_OnMouseDownEvent) Handles AxMapControl1.OnMouseDown</P>
<P>        If ToolBarButton1.Pushed Then <BR>            Dim zoomInRect As AxesriMapControl.AxMapControl<BR>            Dim newRect1 As AxesriMapControl.AxMapControl<BR>            Dim iw As Integer<BR>            AxMapControl1.Extent = AxMapControl1.TrackRectangle<BR>            newRect1 = AxMapControl1.Extent<BR>            iw = zoomInRect.Width<BR>            If (iw > 0) Then<BR>                newRect1.MapScale = 0.5</P>
<P>            Else<BR>                newRect1.MapScale = 0.75<BR>            End If<BR>            AxMapControl1.Extent = newRect1</P>
<P>        ElseIf ToolBarButton2.Pushed Then <BR>            Dim zoomOutRect As AxesriMapControl.AxMapControl<BR>            Dim newRect2 As AxesriMapControl.AxMapControl<BR>            Dim ow, dx, dy As Integer<BR>            zoomOutRect = AxMapControl1.TrackRectangle<BR>            newRect2 = AxMapControl1.Extent<BR>            ow = zoomOutRect.Width<BR>            If (ow > 0) Then<BR>                newRect2.MapScale = 1<BR>            Else<BR>                newRect2.MapScale = 1.5<BR>            End If<BR>            AxMap1.Extent = newRect2</P>
<P>        ElseIf ToolBarButton3.Pushed Then <BR>            AxMapControl1.Pan()<BR>        End If</P>
<P><BR>    End Sub</P>
<P><BR>End Class</P><img src="images/post/smile/dvbbs/em05.gif" /><img src="images/post/smile/dvbbs/em05.gif" />