问题
Assuming the following three-dimensional array is given:
Array
(
[0] => Array
(
[0] => Array
(
[foo] => bar
)
[1] => Array
(
[foo] => bar2
)
[2] => Array
(
[foo] => bar3
)
)
[1] => Array
(
[0] => Array
(
[foo] => baz
)
[1] => Array
(
[foo] => bar
)
[2] => Array
(
[foo] => bar5
)
)
)
Now I need to filter it. If [foo]
is not equal to bar
the corresponding inner array should get removed. The result would be:
Array
(
[0] => Array
(
[0] => Array
(
[foo] => bar
)
)
[1] => Array
(
[1] => Array
(
[foo] => bar
)
)
)
Can this be achieved with array_filter
or array_walk[_recursive]
?
回答1:
Might be more complex than needed but maybe a combination:
$array = array_map(function($v) {
return array_filter($v, function($v) {
return $v['foo'] === 'bar'; }); }, $array);
This should also work:
foreach($array as &$value) {
$value = array_filter($value, function($v) { return $v['foo'] === 'bar'; });
}
You can use a recursive function for deeper or unknown nesting:
function filterNotSomething(&$array, $key, $val) {
foreach($array as $k => $v) {
if(isset($v[$key]) && $v[$key] !== $val) {
unset($array[$k]);
}
elseif(is_array($v)) {
filterNotSomething($array[$k], $key, $val);
}
if(empty($array[$k])) {
unset($array[$k]);
}
}
}
filterNotSomething($array, 'foo', 'bar');
来源:https://stackoverflow.com/questions/34051220/how-to-filter-multi-dimensional-array-with-more-than-two-levels-by-value