我已经创建了一个函数(PHP 8.1)，它允许您将项插入到关联数组或数值数组:

function insertItemsToPosition(array $array, string|int $insertAfterPosition, array $itemsToAdd): array
    {
        $insertAfterIndex = array_search($insertAfterPosition, array_keys($array), true);
        if ($insertAfterIndex === false) {
            throw new \UnexpectedValueException(sprintf('You try to insert items to an array after the key "%s", but this key is not existing in given array. Available keys are: %s', $insertAfterPosition, implode(', ', array_keys($array))));
        }

        $itemsBefore = array_slice($array, 0, $insertAfterIndex + 1);
        $itemsAfter = array_slice($array, $insertAfterIndex + 1);

        return $itemsBefore + $itemsToAdd + $itemsAfter;
    }

代码:

function insertValueAtPosition($arr, $insertedArray, $position) {
    $i = 0;
    $new_array=[];
    foreach ($arr as $key => $value) {
        if ($i == $position) {
            foreach ($insertedArray as $ikey => $ivalue) {
                $new_array[$ikey] = $ivalue;
            }
        }
        $new_array[$key] = $value;
        $i++;
    }
    return $new_array;
}

例子:

$array        = ["A"=8, "K"=>3];
$insert_array = ["D"= 9];

insertValueAtPosition($array, $insert_array, $position=2);
// result ====> ["A"=>8,  "D"=>9,  "K"=>3];

也许看起来不完美，但很有效。

非常简单的2个字符串回答你的问题:

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

首先，你用array_splice向第三个元素插入任何东西，然后给这个元素赋值:

array_splice($array_1, 3, 0 , true);
$array_1[3] = array('sample_key' => 'sample_value');

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
)

使用array_splice而不是array_slice可以减少一次函数调用。

$toto =  array(
  'zero'  => '0',
  'one'   => '1',
  'two'   => '2',
  'three' => '3'
);
$ret = array_splice($toto, 3 );
$toto = $toto +  array("my_key" => "my_value") + $ret;
print_r($toto);

$list = array(
'Tunisia' => 'Tunis',
'Germany' => 'Berlin',
'Italy' => 'Rom',
'Egypt' => 'Cairo'
);
$afterIndex = 2;
$newVal= array('Palestine' => 'Jerusalem');

$newList = array_merge(array_slice($list,0,$afterIndex+1), $newVal,array_slice($list,$afterIndex+1));