It is and it is not difficult. Nonetheless I would recommend
going for screen level help rather than field level help if you
How is described on my site. See Calling WebHelp.
The reason I caution against it is you end up with many
topics and your developers have to program each field to the
relevant topic. We do that in one major program but in another we
have gone for screen level help. In those topics the fields are all
set out in a table with descriptions alongside. The developers find
it easier, I find it easier but best of all, so do our customers.
They can find out about all the fields on the screen while looking
at one topic. With everyone happier, seems to be the way to go.