>我有一个包含多个索引的数组，例如
$arr = array(
1 => array('id' => 0,
'container' => 1
),
2 => array('id' => 1,
'container' => 1
),
3 => array('id' => 2,
'container' => 2
),
4 => array('id' => 3,
'container' => 1
)
);
如何查找并遍历容器为 1 的所有项目，然后循环容器为 2 的所有项目，依此类推。
除了使用错误的数组赋值: .只需将其更改为 => .
然后只需使用 foreach 循环：
$containers = array(1, 2);
foreach($containers as $container) {
foreach ($arr as $value) {
if($container == $value['container']) {
echo "Container: $container : ";
echo $value['id'] . '<br/>';
}
}
}
有很多方法可以做到这一点。这个按给定键重新构造/分组数组 - 如果您无论如何都遍历所有元素，这是可行的。
<?php
$arr = array(
1 => array('id' => 0,
'container' => 1
),
2 => array('id' => 1,
'container' => 1
),
3 => array('id' => 2,
'container' => 2
),
4 => array('id' => 3,
'container' => 1
)
);
$byContainer = groupBy($arr, 'container');
foreach($byContainer as $container=>$items) {
echo $container, "'r'n";
foreach($items as $e) {
echo ' ', $e['id'], "'r'n";
}
}
function groupBy($arr, $key) {
$result = array();
foreach($arr as $e) {
if ( !isset($result[ $e[$key] ]) ) {
$result[ $e[$key] ] = array($e);
}
else {
$result[ $e[$key] ][] = $e;
}
}
return $result;
}
<?php
$arr = array(1 => array('id'=> 0, 'container'=> 1),
2 => array('id'=> 1, 'container'=> 1),
3 => array('id'=> 2, 'container'=> 2),
4 => array('id'=> 3, 'container'=> 1));
$temp = array();
foreach ($arr as $elem) {
foreach ($elem as $k => $v) {
if ($k == 'container') {
$temp[$k][$v][] = $v;
}
}
}
print_r($temp);
?>
工作示例