在数组foreach循环中未设置php创建对象 [英] php unset in array foreach loop creates an object

问题描述

我有一个看起来像这样的大JSON:

I have a big JSON that looks something like this:

{
    "bracers": [
        {
            "id": "Bracers_208",
            "name": "Unearthed Boon"
        }
    ],
    "offHand": [
        {
            "id": "Bracers_208",
            "name": "Unearthed Boon"
        },
        {
            "id": "Weapon123",
            "name": "Some Weapon Boon"
        },
        {
            "id": "Weapon456",
            "name": "Some Other Weapon Boon"
        }
    ],
    "mainHand": [
        {
            "id": "Weapon123",
            "name": "Some Weapon Boon"
        }
    ]
}

我这样解码JSON:

$itemDB = json_decode($json, true);

我现在要做的是从offHand中删除所有已经在mainHand中的条目.因此，我遍历了两者，如果有匹配项，请比较id和unset()的值.

What I want to do now is to remove all entries from offHand that are already in mainHand. So I loop through both, compare the id and unset() the value if there's a match.

foreach($itemDB['offHand'] as $index => $item) {

    foreach($itemDB['mainHand'] as $key => $weapon) {

        if($item['id'] == $weapon['id']) {

            unset($itemDB['offHand'][$index]);

        }

    }

}

然后我再次对其进行编码:

Then I encode it again:

$newJSON = json_encode($itemDB, JSON_PRETTY_PRINT);

删除重复项是可行的，但是offHand数组被更改为如下所示的对象(或assoc数组):

The removal of duplicates works, but the offHand array is changed into an object (or assoc array) that looks like this:

{
    "bracers": [
        {
            "id": "Bracers_208",
            "name": "Unearthed Boon"
        }
    ],
    "offHand": [
        "0": {
            "id": "Bracers_208",
            "name": "Unearthed Boon"
        },
        "2": {
            "id": "Weapon456",
            "name": "Some Other Weapon Boon"
        }
    ],
    "mainHand": [
        {
            "id": "Weapon123",
            "name": "Some Weapon Boon"
        }
    ]
}

为什么会发生这种情况，如何预防呢?

Why does this happen and how can I prevent it?

只是为了澄清一下，如果我删除了unset函数，并且在循环内什么也不做(或者只是向对象添加了一个属性)，则JSON中没有编号的附加键，并且JSON数组就可以了.这就是为什么我得出结论unset导致了这一点的原因.

Just to clarify, if I remove the unset function and just do nothing inside that loops ( or just add a property to the objects), the numbered additional keys in the JSON aren't there and the JSON array is fine. That's why I concluded that unset is causing this.

推荐答案

循环结束后，添加以下代码行以从offHand数组元素中删除键:

After you're loop ends, add the following line of code to remove the keys from the offHand array element:

$itemDB['offHand'] = array_values($itemDB['offHand']);

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