Problem with dynamically built string indexes

Question

I want to dynamically create string indexes, a0,a1,a2... for an array. I can refer to array elements using a formula that returns the indexes, but not when I use strings 'a0', 'a1' etc.

See my code below and corresponding output

$aArray=array(1,2);
foreach ($aArray as  $iIndx => $id) {
      echo '\'a'.$iIndx.'\''.' ';
      $aConditions['\'a'.$iIndx.'\''] = $id;
      echo $aConditions['\'a'.$iIndx.'\''].'<BR>';        
}
echo $aConditions['a0'].' '.$aConditions['a1'];

Running this piece of code results in the following printout:

'a0' 1 'a1' 2

It shows the indexes looks like a0 and a1, and it clearly works to refer to those indexes (the second echo statement in the foreach loop).

However, the last echo statement does not yield any output. No output at all.

Error log gives this notice:

PHP Notice: Undefined index a0 in..... (referring to the last echo line)

The same message for a1.

So it looks like I build indexes that works, and they look like a0 and a1, but they are obviously something else. My problem is I want to refer to those indexes in a different text string, and then I need a perfect match.

Please check my answer below and if it work mark answer as correct :) — Edison Biba
– Edison Biba, Commented Feb 11, 2019 at 10:36

Edison Biba · Accepted Answer · 2019-02-11 10:28:46Z

4

The problem is that your keys are like this 'a0' notice the single quotes in your array.

When you try to access it you use ['a0'] that means that you are accessing a0 key and not 'a0'.

You shouldn't add single quotes to your keys. If you still want to use single quotes then access your keys like this:

$aConditions["'a0'"]

Anyway I think it's a bad idea to use single quotes in your keys. Try to define your keys like this:

 $aConditions['a'.$iIndx] = $id;

And then you can access your values using $aConditions['a0']

edited Feb 11, 2019 at 10:28

answered Feb 11, 2019 at 10:26

Edison Biba

4,4833 gold badges20 silver badges36 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

Greco Jonathan Over a year ago

well spotted :)

ubee Over a year ago

@edisoni Thank´s for your swift answer! Very obvious when I read your explanation. Sometimes (too often) you make it more complex than it need to be....

Edison Biba Over a year ago

I just gave all possible solutions and choices for this problem :)

Federico klez Culloca Over a year ago

@edisoni.1337 I think they meant "you make it more complex" as "one makes it more complex" in this case :)

ubee Over a year ago

Done, and I didn't mean that your answer was too complex but my attempt to build the indexes was....

|

Collectives™ on Stack Overflow

Problem with dynamically built string indexes

1 Answer 1

6 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

6 Comments

Your Answer

Sign up or log in

Post as a guest

Related