PHP: not looping inside a foreach - php

Question

I have this array:
$flavours = array (
0 => array(799390 => 'Banana',),
1 => array(799391 => 'Chocolate',)
);
And now I inside a foreach looping a set from my database. I get 'Banana' from the database and I need the array to give me 799390.
I have tried:
‌‌array_search('Banana', $flavours);
but it does not work unless I add:
‌‌array_search('Banana', $flavours[0]);
But I cannot add [0] as I won't be able to tell in which position 'Banana' flavour is in the array.
Any solution apart from looping again inside a foreach??
Thanks a ton

Answer 1

First, we can use array_walk_recursive() to flatten your array, which just gets rid of your nested arrays.
Next, we use array_flip() to swap the keys/values in the flattened array. This makes it easier to grab the ID for a specific term.
<?php
$flavours = [
[799390 => 'Banana'],
[799391 => 'Chocolate']
];
//flatten array
//Produces: Array ( [799390] => Banana [799391] => Chocolate )
array_walk_recursive($flavours,
function($v, $k) use (&$temp) {
$temp[$k] = $v;
}
);
//flip array. Swaps keys with values.
//Produces: Array ( [Banana] => 799390 [Chocolate] => 799391 )
$flavours = array_flip($temp);
Now you can get the ID pretty easily, such as $flavours['Banana'].
If you have a very very large array, this method may become slow. However, I tested this with 100,000 values on my cheap webhost, and ran this method a few times (20-25 times). It is finishing consistently at around (usually under) 0.1 milliseconds, which is about 0.0014 seconds.

Answer 2

You can insert an if statement to set a condition for your loop as
foreach ($flavours as $key => $value) {
if($key = array_search('Banana', $value)){
echo $key;
}
}
Output
799390

Answer 3

If the word being searched for is a different case many of the usual array methods will not work when trying to find the match, using preg_grep however will allow matches to be found in a case-insensitive manner.
function findflavour( $search, $haystack ){
foreach( $haystack as $index => $arr ){
$res=preg_grep( sprintf( '#%s#i', $search ), $arr );
if( !empty( $res ) ) return array_search( array_values( $res )[0], $arr );
}
return false;
}
$search='BaNanA';
$flavours=array(
array( 799390 => 'Banana' ),
array( 799391 => 'Chocolate' ),
array( 729361 => 'Chilli' ),
array( 879695 => 'Apple' ),
array( 995323 => 'Avacado' ),
array( 528362 => 'Orange' ),
array( 723371 => 'Cherry' ),
);
printf( 'Key:%s', findflavour( $search, $flavours ) );
If there might be multiple elements in the source array with the same value but different IDs a slightly different version of the findflavour function
function findflavour( $search, $haystack, $multiple=false ){
$keys=[];
foreach( $haystack as $index => $arr ){
$res=preg_grep( sprintf( '#%s#i', $search ), $arr );
if( !empty( $res ) ) {
$key=array_search( array_values( $res )[0], $arr );
if( $multiple )$keys[]=$key;
else return $key;
}
}
return $multiple ? $keys : false;
}
$multiple=true;
$search='AVacAdo';
$flavours=array(
array( 799390 => 'Banana' ),
array( 799391 => 'Chocolate' ),
array( 291333 => 'Avacado' ),
array( 729361 => 'Chilli' ),
array( 879695 => 'Apple' ),
array( 995323 => 'Avacado' ),
array( 528362 => 'Orange' ),
array( 723371 => 'Cherry' ),
);
printf( 'Key(s): %s', print_r( findflavour( $search, $flavours, $multiple ), true ) );