Unsetting array values in a foreach loop [duplicate]

Answer 1

$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 => $value) {
    /* … */
}

Now you can delete the item with unset($images[$key]).

Answer 2

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.

Answer 3

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 => $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; $i < count($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();

Answer 4

foreach($images as $key => $image)
{
    if(in_array($image, array(
       'http://i27.tinypic.com/29ykt1f.gif',
       'http://img3.abload.de/img/10nxjl0fhco.gif',
       'http://i42.tinypic.com/9pp2tx.gif',
    ))
    {
        unset($images[$key]);
    }
}

Answer 5

Try that:

foreach ($images[1] as $key => &$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 &$image prevents the loop from creating a copy of the array which would waste memory.

Answer 6

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 & or not for the array item. See this code:

$a=[1,2,3,4,5];
foreach($a as $key=>$val)
{
   if ($key==3) unset($a[$key]);
}
print_r($a);

This prints:

Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [4] => 5
)

So as you can see, if you unset correct thing within the foreach loop, everything works fine.