如何消除重复元素但将最后一个元素保留在数组PHP中答案

【问题标题】：How can I eliminate repeated elements but leaving the last element in the array PHP如何消除重复元素但将最后一个元素保留在数组PHP中
【发布时间】：2022-01-22 17:46:41
【问题描述】：

嗯，我需要能够消除重复的元素，但保留最后一个元素，即消除前面的元素，留下最后一个元素。

这就是我所拥有的

exists: [
 0: {intervention_id: 2, exists: "yes"}
 1: {intervention_id: 2, exists: "no"}
 2: {intervention_id: 2, exists: "yes"}
 3: {intervention_id: 5, exists: "yes"}
 4: {intervention_id: 6, exists: "no"}
 5: {intervention_id: 12, exists: "yes"}
]

我必须删除以前的。

0: {intervention_id: 2, exists: "yes"}
1: {intervention_id: 2, exists: "no"}

然后离开这个

2: {intervention_id: 2, exists: "yes"}

这就是我需要的

exists: [
 0: {intervention_id: 2, exists: "yes"}
 1: {intervention_id: 5, exists: "yes"}
 2: {intervention_id: 6, exists: "no"}
 3: {intervention_id: 12, exists: "yes"}
]

我需要保留最后一个并删除以前的

试试这个，但删除最后一个而不是以前的。

function unique_multidim_array($array, $key) {
    $temp_array = array();
    $i = 0;
    $key_array = array();
   
    foreach($array as $val) {
        if (!in_array($val[$key], $key_array)) {
            $key_array[$i] = $val[$key];
            $temp_array[$i] = $val;
        }
        $i++;
    }
    return $temp_array;
}

【问题讨论】：

Javascript 还是 PHP？
@assembler HI BRO PHP
是什么让一个元素“重复”？只是具有相同的 intervention_id 值？
@AlexHowansky 是的兄弟

标签： javascript php

【解决方案1】：

您可以简单地使用相同的键覆盖当前元素的值。在这种情况下，您将始终获得每个 ID 的最后一个元素

function unique_multidim_array($array, $key) {
    $uniq = [];
    foreach($array as $val) {
        $curVal = $val[$key]; // shortcut of the value
        $uniq[$curVal] = $val; // override previous value if exists
    }
    return array_values($uniq); // array_values to re-index array
}

$exists = [
    ['intervention_id' => 2, 'exists' => 'yes'],
    ['intervention_id' => 2, 'exists' => 'no'],
    ['intervention_id' => 2, 'exists' => 'yes'],
    ['intervention_id' => 5, 'exists' => 'yes'],
    ['intervention_id' => 6, 'exists' => 'no'],
    ['intervention_id' => 12, 'exists' => 'yes'],
];
$uniq = unique_multidim_array($exists, 'intervention_id');
print_r($uniq);

输出：

Array(
    [0] => Array(
            [intervention_id] => 2
            [exists] => yes
        )
    [1] => Array(
            [intervention_id] => 5
            [exists] => yes
        )
    [2] => Array(
            [intervention_id] => 6
            [exists] => no
        )
    [3] => Array(
            [intervention_id] => 12
            [exists] => yes
        )
)

live demo

【讨论】：

【解决方案2】：

$data = [
    [ 'intervention_id' => 2, 'exists' => 'yes' ],
    [ 'intervention_id' => 2, 'exists' => 'no' ],
    [ 'intervention_id' => 2, 'exists' => 'yes' ],
    [ 'intervention_id' => 5, 'exists' => 'yes' ],
    [ 'intervention_id' => 6, 'exists' => 'no' ],
    [ 'intervention_id' => 12, 'exists' => 'yes' ]
];

$map = array_column($data, 'exists', 'intervention_id');

array_walk($map, function (&$value, $key) {
  $value = [ 'intervention_id' => $key, 'exists' => $value ];
}, ARRAY_FILTER_USE_BOTH);

$result = array_values($map);

print_r($result);

【讨论】：