input arguments in a file into rscript

dear listers,

with "rscript", i know how to feed arguments by command line directly,
e.g. "Rscript test.r 10 20". however, if i saved all arguments in a
file, how do i make rscript to take arguments in this file?  "Rscript
test.r < input.txt" doesn't seem to work for me.
(ps: i am using windows)

thanks so much!