Convert Elapsed Time to Seconds

[fred14214]

I need to be able to enter an elapsed time into a text
field. This time then needs to be converted into seconds
and stored in a field in some table.

The user will enter a time (format is h:minutes:seconds)
as such:

0:15:34 (0 hours, 15 minutes, 34 seconds -> 934 seconds
total)

or as another example:

1:02:10 (1 hour, 2 minutes, 10 seconds -> 3730 seconds
total)

Can someone please walk me through this? I imagine this is
VBA related (an Event Procedure), but I'm not sure of the
code or what 'Event' type to out this under for the given
text field.

Thanks.