[Javascript] Check that field doesn't exist

[David T. Lovering]

Yep.  However, I would caution that you'll get an error if you try to telescope a long object description this way, providing that one of the intervening objects isn't defined.  For example:

if (!document.frames["sweetums"].forms[0].myObject) {
  // do something
}

will croak (and not "do something") if frames["sweetums"] doesn't exist, or hasn't been "painted" yet.  Tedious though it may be, sometimes the best way is to do it incrementally, thusly:

  while (!document) { }
  while (!document.frames) { }
  while (!document.frames["sweetums"]) { }
  while (!document.frames["sweetums"].forms[0]) { }
  // you're good to go ...

Ghastly, ain't it?

-- Dave Lovering

Clancy Jones wrote:
> 
> Hi all, how do I check that a field doesn't exist?
> 
> Something like:
> 
> if (!document.form.fieldname){
>     do whatever...
> }
> 
> Cheers,
> Clancy
> 
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