php foreach over an array and assignment of this array

Question

I want to add a value to an array while foreaching it :

foreach ($array as $cell) {
    if ($cell["type"] == "type_list") {
        $cell["list"] = $anObject;
        error_log(print_r($cell, TRUE), 0);
}
error_log(print_r($array, TRUE), 0);

The first printr is ok but the object added disapear when I leave the loop ant print the array.

I guess this is a normal behaviour, what is the best way to work around this "feature" ?

possible duplicate of [php insert value into array of arrays using foreach](http://stackoverflow.com/questions/16491704/php-insert-value-into-array-of-arrays-using-foreach) — kapa, Sep 17 '14 at 19:02

score 11 · Accepted Answer · edited Dec 18 '11 at 15:51

11

Just call $cell by reference like this:

foreach($array as &$cell) {...}

And it should retain the value. Passing by reference.

edited Dec 18 '11 at 15:51

Ross

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answered Dec 18 '11 at 15:49

Indranil

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score 4 · Answer 2 · answered Dec 18 '11 at 15:49

When you iterate over the array, $cell is a copy of the value, not a reference so changing it will not effect the value in the array.

You should either use & to make the $cell a reference:

foreach ($array as &$cell) {
    if ($cell["type"] == "type_list") {
        $cell["list"] = $anObject;
        error_log(print_r($cell, TRUE), 0);
}
error_log(print_r($array, TRUE), 0);

Or access the array items directly using an index.

foreach ($array as $i => $cell) {
    if ($array[$i]["type"] == "type_list") {
        $array[$i]["list"] = $anObject;
        error_log(print_r($array[$i], TRUE), 0);
}
error_log(print_r($array, TRUE), 0);

php foreach over an array and assignment of this array

2 Answers2

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