javascript: find the name of an array key for use in an if..then loop

Question

i'm iterating through and associative array like so:

for (entry in $data[array]) {
  // do some stuff
}

i need to assign a value based on the NAME of a key, like so (pseudo-code):

for (entry in $data[array]) {
  // do some stuff
  if ($data[array][entry]['type'].name = 'thingy') {
    // so some other stuff
  } else {
    // keep doing some stuff
  }
}

thing is, i can't get the zero'th element to cough up its key name such that it can be used as i've typed it (i'm aware it doesn't work...) the array itself looks like this:

$data
(
    [success] => 1
    [findings] =>
        (
            [0] =>
                (
                    [type] => thingy
                    [name] => yo-yo
                    [age] => 1960    
                )
            [1] =>
                (
                    [type] => doohickey
                    [name] => clothespin
                    [age] => 1940    
                )
        )
)

so...essentially what i'm needing to do is do something different if the KEY is a 'type'. basically for every key of 'type', make text red, for example.

what am i missing to make it work? :P i hope i'm making myself clear...

WR!

I find your pseudo-code very confusing. Is the idea that array will be a string variable, with its value being 'success' or 'findings'? And, what do you mean by "the KEY" or "the NAME of a key"? It seems like the "name" or "key" of $data[array][entry]['type'] is simply 'type'. No? I think that real code, with actual JavaScript syntax, would probably be more clear. — ruakh
– ruakh, Commented Dec 13, 2011 at 20:59
Your whole presentation is confused on various accounts. For starters, there's no then in JS. Next, an if is a conditional, not a loop. Sloppiness leads you straight into bugland. Then, you're assigning in a conditional - likely a bug. Also age as 1940 and 1960, that's probably year of birth. - What are you trying to say anyway? — Lumi
– Lumi, Commented Dec 13, 2011 at 21:00
OMG, seriously? please tell me you're joking... this is actual working JS with a simple array pulled from a CSV file! the only 'pseudo' part is the .name i tacked on the end to indicate i was looking for the key's name there. for the tarde-mente: `if (the keys name is 'thingy) {do other stuff} else {do stuff}. — WhiteRau
– WhiteRau, Commented Dec 13, 2011 at 21:17
@WhiteRau: To clarify, the things I found confusing were (1) the pseudo-code (non-JavaScript) object notation; (2) the fact that said object notation, taken literally, seemed to be trying to use arrays as keys; (3) the fact that your initial code used array as a variable-name to refer to a key, reinforcing this notion; and (4) the fact that your whole question was asking how to do something -- pardon me -- something incredibly obvious, so I assumed that I must be misunderstanding you. — ruakh
– ruakh, Commented Dec 14, 2011 at 16:47

Evan Davis · Accepted Answer · 2011-12-13 21:11:46Z

2

The first value in the for (key in set) syntax is, in fact, the key.

for (entry in $data[array]) {
  // do some stuff
  for (thing in $data[array][entry]) {
    if (thing === 'type') {
      //do stuff
    } else {
      // do other stuff
    }
  }
}

answered Dec 13, 2011 at 21:11

Evan Davis

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1 Comment

WhiteRau Over a year ago

i think i tried a flavour of that, but must have fudged it somehow because it wasn't working, so i abandoned it. seeing it now, i know where i went wrong. your way much clearer. thank you very much. :)

sbgoran · Accepted Answer · 2011-12-13 21:23:40Z

1

If I understood your question well then you should try following:

for (entry in $data[array]) {
    // do some stuff
    if ($data[array][entry]['type'] = 'thingy') {
        // so some other stuff
    } else {
        // keep doing some stuff
    }
}

I used your "pseudo-code" syntax because I'm not sure what exactly do you want to achieve, actual JS test code you need help with in your question would be much easier to understand and answer properly.

answered Dec 13, 2011 at 21:23

sbgoran

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1 Comment

WhiteRau Over a year ago

this IS actual JS code. see my comments above. no worries, though; @Mathletics sorted it for me.

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