Unsetting array values in a foreach loop

Question

I have a foreach loop set up to go through my array  check for a certain link  and if it finds it removes that link from the array   My code   foreach  images as  image        if  image     http   i27 tinypic com 29yk345 gif          image     http   img3 abload de img 10nx2340fhco gif          image     http   i42 tinypic com 9pp2456x gif                 unset  images  image              But it doesn t remove the array entires  It s probably something to do with  images  image   as that s not the key of the array entry  only the content  Is there a way to do this without incorporating a counter   Thanks   EDIT  Thanks guys  but now I have another problem where the array entries don t actually get deleted   My new code   foreach  images 1  as  key   gt   image        if  image     http   i27 tinypic com 29yk345 gif        image     http   img3 abload de img 10nx2340fhco gif          image     http   i42 tinypic com 9pp2456x gif                 unset  images  key               images is actuallty a two-dimensional array now hence why I need  images 1   I have checked and it successfully goes around the array elements  and some elements do actually have some of those URLs in that I wish to delete  but they re not getting deleted  This is my  images array   Array        0    gt  Array                        0    gt  useless              1    gt  useless              2    gt  useless              3    gt  useless              4    gt  useless                 1    gt  Array                        0    gt  http   i27 tinypic com 29yk345 gif              1    gt  http   img3 abload de img 10nx2340fhco gif              2    gt  http   img3 abload de img 10nx2340fhco gif              3    gt  http   i42 tinypic com 9pp2456x gif                Thanks

User · Answer

One solution would be to use the key of your items to remove them -- you can both the keys and the values, when looping using foreach.

For instance :

$arr = array(
    'a' => 123,
    'b' => 456,
    'c' => 789, 
);

foreach ($arr as $key => $item) {
    if ($item == 456) {
        unset($arr[$key]);
    }
}

var_dump($arr);

Will give you this array, in the end :

array
  'a' => int 123
  'c' => int 789

Which means that, in your case, something like this should do the trick :

foreach($images as $key => $image)
{
    if($image == 'http://i27.tinypic.com/29yk345.gif' ||
    $image == 'http://img3.abload.de/img/10nx2340fhco.gif' ||
    $image == 'http://i42.tinypic.com/9pp2456x.gif')
    {
        unset($images[$key]);
    }
}

User · Answer

image is in your case the value of the item and not the key  Use the following syntax to get the key too   foreach   images as  key   gt   value                      Now you can delete the item with unset  images  key

User · Answer

To answer the initial question  after your edit   you need to unset  images 1   key     Now some more infos how PHP works  You can safely unset elements of the array in foreach loop  and it doesn t matter if you have  amp  or not for the array item  See this code    a  1 2 3 4 5   foreach  a as  key  gt  val       if   key  3  unset  a  key      print r  a     This prints   Array        0    gt  1      1    gt  2      2    gt  3      4    gt  5     So as you can see  if you unset correct thing within the foreach loop  everything works fine

User · Answer

foreach  images as  key   image                                                      if  image     http   i27 tinypic com 29ykt1f gif             image     http   img3 abload de img 10nxjl0fhco gif             image     http   i42 tinypic com 9pp2tx gif             unset  images  key                                           foreach  images as  key   image  cause  image is the value  so  images  image  make no sense

User · Answer

Try that   foreach   images 1  as  key   gt   amp  image        if  yourConditionGoesHere            unset  images 1   key           unset  image      detach reference after loop     Normally  foreach operates on a copy of your array so any changes you make  are made to that copy and don t affect the actual array   So you need to unset the values via  images  key    The reference on  amp  image prevents the loop from creating a copy of the array which would waste memory

User · Answer

foreach  images as  key   gt   image        if in array  image  array          http   i27 tinypic com 29ykt1f gif           http   img3 abload de img 10nxjl0fhco gif           http   i42 tinypic com 9pp2tx gif                        unset  images  key

User · Answer

You would also need a    i--    after each unset to not skip an element   Because when you unset  item 45   the next element in the for-loop should be  item 45  -  which was  46  before unsetting  If you would not do this  you d always skip an element after unsetting

User · Answer

Sorry for the late response  I recently had the same problem with PHP and found out that when working with arrays that do not use  key   gt   value structure  when using the foreach loop you actual copy the value of the position on the loop variable  in this case  image  Try using this code and it will fix your problem   for   i 0   i  lt  count  images 1     i           if  images 1   i      http   i27 tinypic com 29yk345 gif           images 1   i      http   img3 abload de img 10nx2340fhco gif           images 1   i      http   i42 tinypic com 9pp2456x gif                   unset  images 1   i               var dump  images  die

User · Answer

You can use the index of the array element to remove it from the array  the next time you use the  list variable  you will see that the array is changed  Try something like this foreach  list as  itemIndex   gt   amp  item        if  item  status       false          unset  list  itemIndex

[php] Unsetting array values in a foreach loop

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