In terms of my data structure, I have an array of communications, with each communications_id itself containing three pieces of information: id, score, and content.
I want to implode this array in order to get a comma separated list of ids, how do I do this?
I played with your code to get it working :
function findKey($array, $keySearch)
{
foreach ($array as $key => $item) {
if ($key == $keySearch) {
echo 'yes, it exists';
return true;
} elseif (is_array($item) && findKey($item, $keySearch)) {
return true;
}
}
return false;
}
Try below code:
<?php
$arr = array(
array('city' => 'NewYork', 'cash' => '1000'),
array('city' => 'Philadelphia', 'cash' => '2300'),
array('city' => 'NewYork', 'cash' => '2000'),
);
$newarray = array();
foreach($arr as $ar)
{
foreach($ar as $k => $v)
{
if(array_key_exists($v, $newarray))
$newarray[$v]['cash'] = $newarray[$v]['cash'] + $ar['cash'];
else if($k == 'city')
$newarray[$v] = $ar;
}
}
print_r($newarray);
Output:
Array
(
[NewYork] => Array
(
[city] => NewYork
[cash] => 3000
)
[Philadelphia] => Array
(
[city] => Philadelphia
[cash] => 2300
)
)
Demo:
http://3v4l.org/D8PME
I updated your function and it is giving expected output. Please give a try as following.
function array_key_exists_r($needle, $haystack){
$result = array_key_exists($needle, $haystack);
if ($result)
{
foreach ($haystack as $a=>$v)
{
if($needle == $a)
return $haystack[$a];
if (is_array($v)) {
$result = array_key_exists_r($needle, $v);
}
if ($result) return $result;
}
}
foreach ($haystack as $v) {
if (is_array($v)) {
$result = array_key_exists_r($needle, $v);
}
if ($result) return $result;
}
return $result;
};
The actual problem is you're not assigning the result of array_reverse to anything
// change this
array_reverse($respArr);
// to this
$respArr = array_reverse($respArr);
Update for PHP 5.5
PHP 5.5 introduces
array_columnwhich is a convenient shortcut to a whole class ofarray_mapusage; it is also applicable here.Original answer
You need to make an array of just ids out of your array of communications. Then the implode would be trivial.
Hint: the function for that is
array_map.Solution:
Assumes PHP 5.3, otherwise you 'd have to write the callback as a string.