Сортировка данных по значению на основе сравнения , отражающего букву ( Demo ):
<?php
# the data
$data = array(
0 => array(
'value' => 5,
'label' => 'Akon',
),
1 => array(
'value' => 6,
'label' => 'Angel',
),
2 => array(
'value' => 7,
'label' => 'Britny',
),
3 => array(
'value' => 9,
'label' => 'Mark Anthony',
),
4 => array(
'value' => 8,
'label' => 'Michel',
),
5 => array(
'value' => 4,
'label' => 'Shaggy',
),
6 => array(
'value' => 3,
'label' => 'Smith',
),
);
# the letter
$letter = 'M';
# the value to compare against
$value = function(array $a)
{
$key = 'label';
if (!array_key_exists($key, $a))
{
throw new InvalidArgumentException(sprintf('Key "%s" missing.', $key));
}
return $a[$key];
};
# the comparison
$compare = function($a, $b) use ($letter, $value)
{
$a = $value($a);
$b = $value($b);
if($a[0] != $b[0]) {
if($a[0] === $letter) return -1;
if($b[0] === $letter) return +1;
}
return strcmp($a, $b);
};
# the sort
$sort = function() use ($data, $compare)
{
$r = uasort($data, $compare);
if (!$r)
{
throw new RuntimeException('Sort failed.');
}
return $data;
};
print_r($sort());