I am testing performance and comparing time consumptions in Java and .net and for this I need to calculate in milliseconds. My timestamps are:

time1 = Now.Hour & ":" & Now.Minute & ":" & Now.Second & ":" & Now.Millisecond

when the calculation begins and

time2 = Now.Hour & ":" & Now.Minute & ":" & Now.Second & ":" & Now.Millisecond

How do I subtract the two times when I need milliseconds?