Ignore milliseconds when comparing two datetimes

Question

This is probably a dumb question, but I cannot seem to figure it out. I am comparing the LastWriteTime of two files, however it is always failing because the file I download

Answer 1

Care should be taken, if dt has non-zero microseconds (fractions of millis). Setting only milliseconds to zero is not enough.
To set millis and below to zero (and get a succesfull comparison), the code would be:

dt = dt.AddTicks(-dt.Ticks % TimeSpan.TicksPerSecond); // TimeSpan.TicksPerSecond=10000000