$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));

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。

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;
    }

我最近写了一个函数来做一些类似于你正在尝试的事情，这与clasvdb的答案类似。

function magic_insert($index,$value,$input_array ) {
  if (isset($input_array[$index])) {
    $output_array = array($index=>$value);
    foreach($input_array as $k=>$v) {
      if ($k<$index) {
        $output_array[$k] = $v;
      } else {
        if (isset($output_array[$k]) ) {
          $output_array[$k+1] = $v;
        } else {
          $output_array[$k] = $v;
        }
      } 
    }

  } else {
    $output_array = $input_array;
    $output_array[$index] = $value;
  }
  ksort($output_array);
  return $output_array;
}

基本上，它在一个特定的点插入，但通过向下移动所有项来避免覆盖。

我刚刚创建了一个ArrayHelper类，它可以使数值索引变得非常容易。

class ArrayHelper
{
    /*
        Inserts a value at the given position or throws an exception if
        the position is out of range.
        This function will push the current values up in index. ex. if 
        you insert at index 1 then the previous value at index 1 will 
        be pushed to index 2 and so on.
        $pos: The position where the inserted value should be placed. 
        Starts at 0.
    */
    public static function insertValueAtPos(array &$array, $pos, $value) {
        $maxIndex = count($array)-1;

        if ($pos === 0) {
            array_unshift($array, $value);
        } elseif (($pos > 0) && ($pos <= $maxIndex)) {
            $firstHalf = array_slice($array, 0, $pos);
            $secondHalf = array_slice($array, $pos);
            $array = array_merge($firstHalf, array($value), $secondHalf);
        } else {
            throw new IndexOutOfBoundsException();
        }

    }
}

例子:

$array = array('a', 'b', 'c', 'd', 'e');
$insertValue = 'insert';
\ArrayHelper::insertValueAtPos($array, 3, $insertValue);

开始$数组:

Array ( 
    [0] => a 
    [1] => b 
    [2] => c 
    [3] => d 
    [4] => e 
)

结果:

Array ( 
    [0] => a 
    [1] => b 
    [2] => c 
    [3] => insert 
    [4] => d 
    [5] => e 
)

这是PHP 7.1中的另一个解决方案

     /**
     * @param array $input    Input array to add items to
     * @param array $items    Items to insert (as an array)
     * @param int   $position Position to inject items from (starts from 0)
     *
     * @return array
     */
    function arrayInject( array $input, array $items, int $position ): array 
    {
        if (0 >= $position) {
            return array_merge($items, $input);
        }
        if ($position >= count($input)) {
            return array_merge($input, $items);
        }

        return array_merge(
            array_slice($input, 0, $position, true),
            $items,
            array_slice($input, $position, null, true)
        );
    }