访问嵌套的JSON密钥而不循环

Question

我有一个JSON字符串,如下面给出的存储在其中的字符串$json.我想在category_id不使用循环的情况下访问第一个.我该如何访问它？

$json = '{"outfits": [{"1": [{"category_id": "women_jeans", "product_id": 464540467}, {"category_id": "women_tops", "product_id": 487351815}, {"category_id": "women_coats", "product_id": 493322686}, {"category_id": "women_bags", "product_id": 483902882}, {"category_id": "women_shoes", "product_id": 492772225}]}]}';
$outfits = json_decode($json);

Answer 1

试试下面的代码.

$json = '{"outfits": [{"1": [{"category_id": "women_jeans", "product_id": 464540467}, {"category_id": "women_tops", "product_id": 487351815}, {"category_id": "women_coats", "product_id": 493322686}, {"category_id": "women_bags", "product_id": 483902882}, {"category_id": "women_shoes", "product_id": 492772225}]}]}';
$outfits = json_decode($json,true);
echo "Category 1: ".$outfits["outfits"][0][1][0]['category_id'];
echo "Category 2: ".$outfits["outfits"][0][1][1]['category_id'];

产量

women_jeans
women_tops

您还可以使用以下功能查找特定值.

$array = $outfits["outfits"][0][1];
$key = "product_id";
$val = "464540467";

function whatever($array, $key, $val) {
    foreach ($array as $item)
        if (isset($item[$key]) && $item[$key] == $val)
            echo $item['category_id'];
    return false;
}

whatever($array,$key,$val);

产量

women_jeans

如果你想在没有循环的情况下获得category_id,true那么请在下面使用.

$array = $outfits->outfits[0]->{1};
$category1 = $array[0]->category_id;