PHP:如何删除索引后的所有数组元素

Question

是否可以删除索引后的所有数组元素？

$myArrayInit = array(1=>red, 30=>orange, 25=>velvet, 45=>pink);

现在一些"神奇"

$myArray = delIndex(30, $myArrayInit);

要得到

$myArray = array(1=>red, 30=>orange); 

由于钥匙$myArray不是连续的,我没有看到机会array_slice()

Please note:钥匙必须保留!+我只知道偏移钥匙!!

Answer 1

不使用循环.

<?php
    $myArrayInit = [1 => 'red', 30 => 'orange', 25 => 'velvet', 45 => 'pink']; //<-- Your actual array
    $offsetKey = 25; //<--- The offset you need to grab

    //Lets do the code....
    $n = array_keys($myArrayInit); //<---- Grab all the keys of your actual array and put in another array
    $count = array_search($offsetKey, $n); //<--- Returns the position of the offset from this array using search
    $new_arr = array_slice($myArrayInit, 0, $count + 1, true);//<--- Slice it with the 0 index as start and position+1 as the length parameter.
    print_r($new_arr);

Output :

Array
(
    [1] => red
    [30] => orange
    [25] => velvet
)

Answer 2

尝试

$arr = array(1=>red, 30=>orange, 25=>velvet, 45=>pink);
$pos = array_search('30', array_keys($arr));
$arr= array_slice($arr,0,$pos+1,true);
echo "<pre>";
print_r($arr);

查看演示