试试这个:

$colors = array('red', 'blue', 'yellow');

$colors = insertElementToArray($colors, 'green', 2);


function insertElementToArray($arr = array(), $element = null, $index = 0)
{
    if ($element == null) {
        return $arr;
    }

    $arrLength = count($arr);
    $j = $arrLength - 1;

    while ($j >= $index) {
        $arr[$j+1] = $arr[$j];
        $j--;
    }

    $arr[$index] = $element;

    return $arr;
}

试试这个:

$colors = array('red', 'blue', 'yellow');

$colors = insertElementToArray($colors, 'green', 2);


function insertElementToArray($arr = array(), $element = null, $index = 0)
{
    if ($element == null) {
        return $arr;
    }

    $arrLength = count($arr);
    $j = $arrLength - 1;

    while ($j >= $index) {
        $arr[$j+1] = $arr[$j];
        $j--;
    }

    $arr[$index] = $element;

    return $arr;
}

没有本地PHP函数(据我所知)可以完全完成您的请求。

我已经写了2个我认为适合目的的方法:

function insertBefore($input, $index, $element) {
    if (!array_key_exists($index, $input)) {
        throw new Exception("Index not found");
    }
    $tmpArray = array();
    $originalIndex = 0;
    foreach ($input as $key => $value) {
        if ($key === $index) {
            $tmpArray[] = $element;
            break;
        }
        $tmpArray[$key] = $value;
        $originalIndex++;
    }
    array_splice($input, 0, $originalIndex, $tmpArray);
    return $input;
}

function insertAfter($input, $index, $element) {
    if (!array_key_exists($index, $input)) {
        throw new Exception("Index not found");
    }
    $tmpArray = array();
    $originalIndex = 0;
    foreach ($input as $key => $value) {
        $tmpArray[$key] = $value;
        $originalIndex++;
        if ($key === $index) {
            $tmpArray[] = $element;
            break;
        }
    }
    array_splice($input, 0, $originalIndex, $tmpArray);
    return $input;
}

虽然速度更快，而且可能更节省内存，但这只适用于不需要维护数组键的地方。

如果你确实需要维护密钥，下面的方法会更合适;

function insertBefore($input, $index, $newKey, $element) {
    if (!array_key_exists($index, $input)) {
        throw new Exception("Index not found");
    }
    $tmpArray = array();
    foreach ($input as $key => $value) {
        if ($key === $index) {
            $tmpArray[$newKey] = $element;
        }
        $tmpArray[$key] = $value;
    }
    return $input;
}

function insertAfter($input, $index, $newKey, $element) {
    if (!array_key_exists($index, $input)) {
        throw new Exception("Index not found");
    }
    $tmpArray = array();
    foreach ($input as $key => $value) {
        $tmpArray[$key] = $value;
        if ($key === $index) {
            $tmpArray[$newKey] = $element;
        }
    }
    return $tmpArray;
}

要将元素插入到具有字符串键的数组中，您可以这样做:

/* insert an element after given array key
 * $src = array()  array to work with
 * $ins = array() to insert in key=>array format
 * $pos = key that $ins will be inserted after
 */ 
function array_insert_string_keys($src,$ins,$pos) {

    $counter=1;
    foreach($src as $key=>$s){
        if($key==$pos){
            break;
        }
        $counter++;
    } 

    $array_head = array_slice($src,0,$counter);
    $array_tail = array_slice($src,$counter);

    $src = array_merge($array_head, $ins);
    $src = array_merge($src, $array_tail);

    return($src); 
} 

在数组开头添加元素的提示:

$a = array('first', 'second');
$a[-1] = 'i am the new first element';

然后:

foreach($a as $aelem)
    echo $a . ' ';
//returns first, second, i am...

but:

for ($i = -1; $i < count($a)-1; $i++)
     echo $a . ' ';
//returns i am as 1st element

在做了几天之后，这是我能找到的最简单的解决方案。

$indexnumbertoaddat // this is a variable that points to the index # where you 
want the new array to be inserted

$arrayToAdd = array(array('key' => $value, 'key' => $value)); //this is the new 
 array and it's values that you want to add. //the key here is to write it like 
 array(array('key' =>, since you're adding this array inside another array. This 
 is the point that a lot of answer left out. 

array_splice($originalArray, $indexnumbertoaddatt, 0, $arrayToAdd); //the actual 
splice function. You're doing it to $originalArray, at the index # you define, 
0 means you're just shifting all other index items down 1, and then you add the 
new array.