Need an example of how to use "try" and "catch"

Pete pete at mollysrevenge.com
Thu Mar 22 14:49:38 EDT 2012


Interesting, never thought of that.  Is there an advantage to doing that
over just issuing the database call and checking for an error right after?

I've mostly thought of try/catch for as a debugging tool.  I also use it
any place where I put together a command in a variable and execute the
command with a do statement.

Pete

On Thu, Mar 22, 2012 at 11:30 AM, Bob Sneidar <bobs at twft.com> wrote:

> I use it to determine if there has been an error executing a sequel query
> for example. All my database calls go inside a try catch statement. If you
> put it into a repeat loop, you can test to see if perhaps you have been
> disconnected, or if a runtime error occurred due to a bad query, and then
> act accordingly, either try to reconnect if disconnected, or bail out
> gracefully if a runtime error has occurred.
>
> Bob
>
>
> On Mar 22, 2012, at 10:33 AM, Michael Doub wrote:
>
> > Does anyone have any guidelines as to when you should use the try and
> catch structure?   I don't really know when or when not to use it.
> >
> > -= Mike
> >
> >
> >
> > On Mar 22, 2012, at 1:21 PM, Jim Hurley wrote:
> >
> >> Thanks Peter.
> >>
> >> The problem now is what do these bloody error numbers translate into.
> >> Is the a list somewhere?
> >>
> >> When I try:
> >>
> >> on mouseUP
> >>  try
> >> put the cantdelete of me into temp
> >> catch tErr
> >> --- if tErr is ??????
> >> end try
> >> end mouseUP
> >>
> >> I get an error of 348,0,0
> >>
> >> Jim
> >>
> >>
> >>
> >>
> >>> Peter Brigham wrote:
> >>>
> >>> The syntax for the try construction is
> >>>
> >>> try
> >>>  <command here>
> >>> catch tError
> >>>  <other commands here>
> >>> end try
> >>>
> >>> and the error number is put into the variable tError. So the <other
> commands> could be, eg,
> >>>
> >>>  if tError = 314 then
> >>>     answer "range error in loading array"
> >>>  else if ...
> >>>     etc.
> >>>  end if
> >>>
> >>> -- Peter
> >>>
> >>> Peter M. Brigham
> >>>
> >>> pmbrig at gmail.com
> >>> http://home.comcast.net/~pmbrig
> >>>
> >>
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-- 
Pete
Molly's Revenge <http://www.mollysrevenge.com>



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