可以用waitfor组件. 下面是国外的一名asp作者的语句:

Developer's often need to have their apps wait a specified number of
seconds, detect if a file exists within a particular timeout or wait
for exclusive file access within a specified timeout. This component
is designed to allow developers to do that from ASP.

To install

a) Move the component into the subdirectory you want to store it in
b) Type regsvr32 waitfor.dll
c) Run markwait.exe to mark the registry
d) Move the example script into a directory off your Web server
e) Modify the example for your own use

Unfortunately I cannot PRovide free support for this free component.

Best wishes,

Stephen