多重buffer问题，HELP 谢谢

It is not convenient for me to type Chinese, sorry if you do not like it.

I am using ArcGIS 9 with service pack 2 and VB 6. I plan to creat a buffer(multiRingBuffer, 30;60;90 meters) for my stream/pond shape file.

Originally, I think I can use GeoProcessing's multiRingBuffer, but sample codes in Geoprocessing is not that clear to use. As shows below, I am not sure where the user installed ArcGIS in his computer, how could I set the toolbox in my code?

Any suggestions would be greatly appreciated.

Thank you for your attention and help.

Yanli
Sub RunGPTool()
'Create the Geoprocessor object
Dim GP As Object
Set GP = CreateObject("esriGeoprocessing.GpDispatch.1")

'Set the toolbox
GP.Toolbox = "D:\ArcGIS\ArcToolbox\Toolboxes\Analysis Tools.tbx"

'Execute tools
GP.Clip "D:\Workspace\Portland.mdb\Region\streets", _
"D:\Workspace\Portland.mdb\Region\downtown", "D:\Workspace\Portland.mdb\Region\dt_streets"

GP.Buffer "D:\Workspace\Portland.mdb\Region\dt_streets", _
"D:\Workspace\Portland.mdb\Region\dt_streetsbuf", "500"
End Sub

ArcGIS的安装位置是可以通过注册表来读取的。

HKEY_LOCAL_MACHINE\SOFTWARE\ESRI\ArcGIS下面有一个条目叫InstallDir。