CODE
<?php
$a = array('31','01','02','03','30','31','01','02');
$b = array('7','7','7','7','8','8','8','8');
$c = array_combine($a,$b);
var_dump($c);
?>
RESULT It ignores the duplicate values with the same key array(5) { [31]=> string(1) "8" ["01"]=> string(1) "8" ["02"]=> string(1) "8" ["03"]=> string(1) "7" [30]=> string(1) "8" }
WHAT I NEED
I need to make an associative array with keys and duplicate values separated by comma.(Here: 31th key has two values 7 and 8)
Your task can be solved by a simple foreach
:
$c = [];
foreach ($a as $key => $value) {
if (!isset($c[$value])) {
// there's NO key `$value` in `$c` - add it with initial value
$c[$value] = [];
}
// add new value to this key
$c[$value][] = $b[$key];
}
// Output
// Array ( [31] => Array ( [0] => 7 [1] => 8 ) [01] => Array ( [0] => 7 [1] => 8 ) [02] => Array ( [0] => 7 [1] => 8 ) [03] => Array ( [0] => 7 ) [30] => Array ( [0] => 8 )
Version for comma separated values:
foreach ($a as $key => $value) {
if (!isset($c[$value])) {
// there's NO key `$value` in `$c` - add it with initial value
$c[$value] = $b[$key];
} else {
$c[$value] .= ',' . $b[$key];
}
}
// Output:
// Array ( [31] => 7,8 [01] => 7,8 [02] => 7,8 [03] => 7 [30] => 8 )