假设我们有两个数组:

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

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

现在,我想在每个数组的第三个元素后插入数组('sample_key' => 'sample_value')。我该怎么做呢?


当前回答

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
)
*/




其他回答

我这样做


    $slightly_damaged = array_merge(
        array_slice($slightly_damaged, 0, 4, true) + ["4" => "0.0"], 
        array_slice($slightly_damaged, 4, count($slightly_damaged) - 4, true)
    );

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 
)

这里有一个你可以使用的简单函数。只要插进去就行了。

这是按索引插入,而不是按值插入。

您可以选择传递该数组,或者使用已经声明的数组。

较新的、较短的版本:

   function insert($array, $index, $val)
   {
       $size = count($array); //because I am going to use this more than one time
       if (!is_int($index) || $index < 0 || $index > $size)
       {
           return -1;
       }
       else
       {
           $temp   = array_slice($array, 0, $index);
           $temp[] = $val;
           return array_merge($temp, array_slice($array, $index, $size));
       }
   }

更老、更长的版本:

  function insert($array, $index, $val) { //function decleration
    $temp = array(); // this temp array will hold the value 
    $size = count($array); //because I am going to use this more than one time
    // Validation -- validate if index value is proper (you can omit this part)       
        if (!is_int($index) || $index < 0 || $index > $size) {
            echo "Error: Wrong index at Insert. Index: " . $index . " Current Size: " . $size;
            echo "<br/>";
            return false;
        }    
    //here is the actual insertion code
    //slice part of the array from 0 to insertion index
    $temp = array_slice($array, 0, $index);//e.g index=5, then slice will result elements [0-4]
    //add the value at the end of the temp array// at the insertion index e.g 5
    array_push($temp, $val);
    //reconnect the remaining part of the array to the current temp
    $temp = array_merge($temp, array_slice($array, $index, $size)); 
    $array = $temp;//swap// no need for this if you pass the array cuz you can simply return $temp, but, if u r using a class array for example, this is useful. 
  
     return $array; // you can return $temp instead if you don't use class array
}

使用的例子:

//1
$result = insert(array(1,2,3,4,5),0, 0);
echo "<pre>";
echo "<br/>";
print_r($result);
echo "</pre>";
//2
$result = insert(array(1,2,3,4,5),2, "a");
echo "<pre>";
print_r($result);
echo "</pre>";
//3
$result = insert(array(1,2,3,4,5) ,4, "b");
echo "<pre>";
print_r($result);
echo "</pre>";
//4
$result = insert(array(1,2,3,4,5),5, 6);
echo "<pre>";
echo "<br/>";
print_r($result);
echo "</pre>";

预期结果:

//1
Array
(
    [0] => 0
    [1] => 1
    [2] => 2
    [3] => 3
    [4] => 4
    [5] => 5
)
//2
Array
(
    [0] => 1
    [1] => 2
    [2] => a
    [3] => 3
    [4] => 4
    [5] => 5
)
//3
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => b
    [5] => 5
)

//4
Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
    [4] => 5
    [5] => 6
)

如果你不知道你想在位置3插入它,但你知道你想在后面插入它的键,在看到这个问题后,我想出了这个小函数。

/**
     * Inserts any number of scalars or arrays at the point
     * in the haystack immediately after the search key ($needle) was found,
     * or at the end if the needle is not found or not supplied.
     * Modifies $haystack in place.
     * @param array &$haystack the associative array to search. This will be modified by the function
     * @param string $needle the key to search for
     * @param mixed $stuff one or more arrays or scalars to be inserted into $haystack
     * @return int the index at which $needle was found
     */                         
    function array_insert_after(&$haystack, $needle = '', $stuff){
        if (! is_array($haystack) ) return $haystack;

        $new_array = array();
        for ($i = 2; $i < func_num_args(); ++$i){
            $arg = func_get_arg($i);
            if (is_array($arg)) $new_array = array_merge($new_array, $arg);
            else $new_array[] = $arg;
        }

        $i = 0;
        foreach($haystack as $key => $value){
            ++$i;
            if ($key == $needle) break;
        }

        $haystack = array_merge(array_slice($haystack, 0, $i, true), $new_array, array_slice($haystack, $i, null, true));

        return $i;
    }

这里是一个代码板小提琴看到它的行动:http://codepad.org/5WlKFKfz

注意:array_splice()会比array_merge(array_slice())更有效,但这样你插入的数组的键就会丢失。叹息。

Array_slice()可以用来提取数组的部分,联合数组操作符(+)可以重新组合这些部分。

$res = array_slice($array, 0, 3, true) +
    array("my_key" => "my_value") +
    array_slice($array, 3, count($array)-3, true);

这个例子:

$array = array(
  'zero'  => '0',
  'one'   => '1',
  'two'   => '2',
  'three' => '3',
);
$res = array_slice($array, 0, 3, true) +
    array("my_key" => "my_value") +
    array_slice($array, 3, count($array) - 1, true) ;
print_r($res);

给:

Array
(
    [zero] => 0
    [one] => 1
    [two] => 2
    [my_key] => my_value
    [three] => 3
)