我需要一些可以在键之前，替换，之后插入的东西;如果没有找到目标键，则在数组的开头或结尾添加。默认是在键后插入。

新功能

/**
 * Insert element into an array at a specific key.
 *
 * @param array $input_array
 *   The original array.
 * @param array $insert
 *   The element that is getting inserted; array(key => value).
 * @param string $target_key
 *   The key name.
 * @param int $location
 *   1 is after, 0 is replace, -1 is before.
 *
 * @return array
 *   The new array with the element merged in.
 */
function insert_into_array_at_key(array $input_array, array $insert, $target_key, $location = 1) {
  $output = array();
  $new_value = reset($insert);
  $new_key = key($insert);
  foreach ($input_array as $key => $value) {
    if ($key === $target_key) {
      // Insert before.
      if ($location == -1) {
        $output[$new_key] = $new_value;
        $output[$key] = $value;
      }
      // Replace.
      if ($location == 0) {
        $output[$new_key] = $new_value;
      }
      // After.
      if ($location == 1) {
        $output[$key] = $value;
        $output[$new_key] = $new_value;
      }
    }
    else {
      // Pick next key if there is an number collision.
      if (is_numeric($key)) {
        while (isset($output[$key])) {
          $key++;
        }
      }
      $output[$key] = $value;
    }
  }
  // Add to array if not found.
  if (!isset($output[$new_key])) {
    // Before everything.
    if ($location == -1) {
      $output = $insert + $output;
    }
    // After everything.
    if ($location == 1) {
      $output[$new_key] = $new_value;
    }

  }
  return $output;
}

输入代码

$array_1 = array(
  '0' => 'zero',
  '1' => 'one',
  '2' => 'two',
  '3' => 'three',
);
$array_2 = array(
  'zero'  => '0',
  'one'   => '1',
  'two'   => '2',
  'three' => '3',
);

$array_1 = insert_into_array_at_key($array_1, array('sample_key' => 'sample_value'), 2, 1);
print_r($array_1);
$array_2 = insert_into_array_at_key($array_2, array('sample_key' => 'sample_value'), 'two', 1);
print_r($array_2);

输出

Array
(
    [0] => zero
    [1] => one
    [2] => two
    [sample_key] => sample_value
    [3] => three
)
Array
(
    [zero] => 0
    [one] => 1
    [two] => 2
    [sample_key] => sample_value
    [three] => 3
)

最简单的解决方案，如果你想在某个键后插入(一个元素或数组):

function array_splice_after_key($array, $key, $array_to_insert)
{
    $key_pos = array_search($key, array_keys($array));
    if($key_pos !== false){
        $key_pos++;
        $second_array = array_splice($array, $key_pos);
        $array = array_merge($array, $array_to_insert, $second_array);
    }
    return $array;
}

如果你有:

$array = [
    'one' => 1,
    'three' => 3
];
$array_to_insert = ['two' => 2];

和执行:

$result_array = array_splice_after_key($array, 'one', $array_to_insert);

你会有:

Array ( 
    ['one'] => 1 
    ['two'] => 2 
    ['three'] => 3 
)

这是一个老问题，但我在2014年发表了一篇评论，经常回到这个问题。我想我应该留下一个完整的答案。这不是最短的解决方案，但很容易理解。

在关联数组中插入一个新值，在有编号的位置，保留键并保持顺序。

$columns = array(
    'id' => 'ID',
    'name' => 'Name',
    'email' => 'Email',
    'count' => 'Number of posts'
);

$columns = array_merge(
    array_slice( $columns, 0, 3, true ),     // The first 3 items from the old array
    array( 'subscribed' => 'Subscribed' ),   // New value to add after the 3rd item
    array_slice( $columns, 3, null, true )   // Other items after the 3rd
);

print_r( $columns );

/*
Array ( 
    [id] => ID 
    [name] => Name 
    [email] => Email 
    [subscribed] => Subscribed 
    [count] => Number of posts 
)
*/

对于第一个数组，使用array_splice():

$array_1 = array(
  '0' => 'zero',
  '1' => 'one',
  '2' => 'two',
  '3' => 'three',
);

array_splice($array_1, 3, 0, 'more');
print_r($array_1);

输出:

Array(
    [0] => zero
    [1] => one
    [2] => two
    [3] => more
    [4] => three
)

对于第二个，没有顺序，所以你只需要做:

$array_2['more'] = '2.5';
print_r($array_2);

把钥匙按你想要的排序。

这可以通过array.splice()来实现。请注意，array_splice或array_merge不会为关联数组保留键。因此使用array_slice和'+'操作符来连接两个数组。

详情请点击这里

$array_1 = array(
    '0' => 'zero',
    '1' => 'one',
    '2' => 'two',
    '3' => 'three',
  );
  
  $array_2 = array(
    'zero'  => '0',
    'one'   => '1',
    'two'   => '2',
    'three' => '3',
  );
  $index = 2;
  $finalArray = array_slice($array_1, 0, $index, true) +
                $array2  +
                array_slice($array_2, $index, NULL, true);
print_r($finalArray);
/*
Array
(
    [0] => zero
    [1] => one
    [10] => grapes
    [z] => mangoes
    [two] => 2
    [three] => 3
)
*/

这是一种更好的方法，如何在数组的某个位置插入项目。

function arrayInsert($array, $item, $position)
{
    $begin = array_slice($array, 0, $position);
    array_push($begin, $item);
    $end = array_slice($array, $position);
    $resultArray = array_merge($begin, $end);
    return $resultArray;
}