Undefined Error Issue

[vozzek]

Hi all,

Quick problem here:

I have a form containing zero to five drop-down label selections (option_a, option_b, etc...) depending upon what's pulled from my SQL database. So in short, sometimes the page contains 1, 2 or more of these labels... other times it contains none at all.

I want to validate the info in those dropdowns, but first I need to see if each option exists.

First I tried this code:

  var valid = 1;
  var errmsg = "";
  var errmsg1 = "Please make sure all drop-down selections are made.";
  var frm = document.addtocartform;
  if (frm.option_a.value != undefined) {
     if (frm.option_a.value == "Please Select") {
        errmsg = errmsg1;
        valid = 0;
        }
     }

If option_a exists, this works fine. If option_a doesn't exist, it errors out. The undefined isn't doing anything for me.

I tried using TYPEOF, but that doesn't seem to work either. Substitute the above 'if' statement with the following code:

if (typeof frm.option_a.value != 'undefined') {

Any ideas?
Thanks in advance.

[Dasty]

if (frm.option_a) {
  // from now you can test any of frm.option_a's properties (like .value etc)
  if (frm.option_a.value == "Please Select") {
    errmsg = errmsg1;
    valid = 0;
  }
}

You can not test/access object's property if object does not exist - so test if object is present first . (that's why you got your error message)

[vozzek]

Rock on!!!

Thanks bro, I should've thought of that. Worked like a charm.

-Danny