PHP array slice multiple array non functional

Question

The following slices $scpar into two types one containing the first 9 and the second containing former comma separated values from 10 to 18.

$scpar9 = array_slice($scpar,0,9);
      $scpar18 = array_slice($scpar,9,18);

We then use a foreach and use an id parameter $sid to get the same comma separated value from other fields.

foreach ($scpar9 as $sid => $scpar) {

Information is then taken from other fields like this.

<b>'.$scpar.'</b> '.$sccomp[$sid].$scmen[$sid].

That all works fine, the problem is with the second 9 fields.

foreach ($scpar18 as $sid => $scpar) {
<b>'.$scpar.'</b> '.$sccomp[$sid].$scmen[$sid].

The field $scpar is correct but the ones containing the [$sid] are starting from the first result not the 9th.

Any ideas?

Marvellous

why are you slicing these into 2 arrays? wouldn't a `for` loop be better? — Daniel A. White, Jul 18 '11 at 13:20

score 1 · Answer 1 · edited Jul 18 '11 at 13:25

array_slice() creates new arrays containing the values from the original arrays, not the keys. Using the keys in the foreach loop is meaningless in the context of the original array, since these are the keys from the new slice arrays.

Use array_slice($scpar, 9, 18, true) to copy the keys as well, not just the values:

$scpar18 = array_slice($scpar, 9, 18, true);
                                  #    ^^^ preserve keys

score 1 · Answer 2 · answered Jul 18 '11 at 13:21

1

If you want to preserve the keys ($sid), you need to set the fourth param to true for array_slice, see http://php.net/manual/en/function.array-slice.php

answered Jul 18 '11 at 13:21

Stefan H Singer

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score 1 · Accepted Answer · answered Jul 18 '11 at 13:23

1

you need to use preserve_keys

preserve_keys : Note that array_slice() will reorder and reset the array indices by default. You can change this behaviour by setting preserve_keys to TRUE.

   $scpar18 = array_slice($scpar,9,18, true);

answered Jul 18 '11 at 13:23

Haim Evgi

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PHP array slice multiple array non functional

3 Answers3