Comparing Multi and single dimensional arrays in php - php

Question

I am new to php just playing with some array.
I Want to get following things from the array which are of different dimensional
The following is the Multidimensional Array
$a = array(
array(
'productsid' => 90,
'CouponID' => 50
),
array(
'productsid' => 80,
'CouponID' => 95
),
array(
'productsid' => 80,
'CouponID' => 95
));
The following is Single dimensional array:
$b = array(80,90,95);
I want to compare only the productsid index of the array with the single dimensional array and wants to fetch the data which is equal to it.
I Have tried the following loop to print but it only gives the values of the productsid only but I want that full array. But only by comparing the Productid with the second array.
for ($i = 0; $i < 3; $i++) {
foreach ($a[$i] as $key => $value) {
foreach ($b as $c) {
if ($value == $c) {
echo $value .'<br>';
}
}
} }

Answer 1

Looks like you're looking for in_array():
$result = array();
foreach($a as $item)
if(in_array($item['productsid'], $b))
$result []= $item;
or, in a more concise (but less readable IMO) way:
$result = array_filter($a, function($item) use($b) {
return in_array($item['productsid'], $b);
});
For your test data it's doesn't matter much, but if your arrays are big and/or this loop is going to run many times, you can achieve better performance by converting the lookup array into a hash table and using O(1) key lookup instead of linear array search:
$bs = array_flip($b);
$result = array_filter($a, function($item) use($bs) {
return isset($bs[$item['productsid']]);
});

Answer 2

$b = array(80,90,95);
$c = array();
foreach($a as $val) {
if(in_array($val['productsid'],$b)) {
$c[] = $val;
}
}
echo "<pre>";
print_r($c);

Answer 3

Try this:
foreach($a as $ar) {
if (in_array($ar['productsid'], $b))
print_r($ar);
}