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I would like to know if it is possible to get the x-value position (ie 2nd) in a variable variable array reference.

the code below works for the 1st array but not the 2nd. 

// WORKS FINE //
$my1stArray= array( 'red', 'green', 'blue');
$var_1st = 'my1stArray';

// for each lopp of var var works fine
echo " - my1stArray Values - <br>";
foreach ($$var_1st as $k => $v){
echo $k." : ".$v." <br>";
}
// direct access also works
echo "my1stArray 3rd value: ".${$var_1st}[2]."<br>";

// Not so good! //
$my2ndArray = array(
    'color' => '#ff0000',
    'face' => 'helvetica',
    'size' => '+5',
);
$var_2nd = 'my2ndArray';

// for each lopp of var_2nd works fine
echo "<br> - my2ndArray Values - <br>";
foreach ($$var_2nd as $k => $v){
echo $k." : ".$v." <br>";
}
/** try to access 2nd value in array with position **/
echo "my2ndArray 2rd value: ".${$var_2nd[1]}[0]."<br>";
echo "my2ndArray 2rd value: ".${$var_2nd}[1][0]."<br>";
Brian Tompsett - 汤莱恩
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art vanderlay
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  • `foreach ($$var_2nd as $k => $v){ echo $k." : ".$v."
    "; }` works, right? The answer to this question lies on its output...     – bfavaretto Sep 05 '12 at 02:35
  • @bfavaretto yes I can do a count own the foreach, I was just wondering if there is a direct method rather than a foreach loop. thx Art – art vanderlay Sep 05 '12 at 02:42
  • No, if you have an associative array you cannot access it by position (unless you count inside your loop and break when the count reaches the desired position). – bfavaretto Sep 05 '12 at 02:50

2 Answers2

1

Your last example in your code is not working for the same reason that the following code does not work:

$a = array('akey'=>'a','bkey'=>'b');
echo $a[0];

The reason is the key is set to a string and must be accessed as such. To fix my example I would need to change it to:

$a = array('akey'=>'a','bkey'=>'b');
echo $a['akey'];

To fix your example you need to change your last echo so that it references the key as a string:

echo "my2ndArray 2rd value: ".${$var_2nd}['color']."<br>";
Brett
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  • thx @brett, I had the ref by key ie['color'] working already, however the incoming key is unknown, only the order in the array. I am looking for a better way to ref the key by position if the key is set with a string. currently I need to add the keys to an array, get the 2nd value, then search the primary array for the value['color']? thx Art – art vanderlay Sep 05 '12 at 02:39
  • If you don't care about the keys only the position. You could use [array_values](http://php.net/array_values) to have the keys replaced with there numerical position. – Brett Sep 05 '12 at 03:01
1

Well, in the comments I said "no, you can't", but there is actually a way. Here is an example (without variable variables):

$my2ndArray = array(
    'color' => '#ff0000',
    'face' => 'helvetica',
    'size' => '+5',
);
$keys = array_keys($my2ndArray);
echo "my2ndArray 2nd value: " . $my2ndArray[$keys[1]]  . "<br>";

Doesn't look very nice, but should work. Not that if you ever sort the array, the key indexes will change.

Another way to do that would be using a counter and a loop as I mentioned in the comments. But that would be even uglier...

bfavaretto
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