如何将 JSON 字符串转换为数组（PHP）？答案

【问题标题】：How to convert a JSON string into an array (PHP)?如何将 JSON 字符串转换为数组（PHP）？
【发布时间】：2010-02-26 22:00:02
【问题描述】：

使用下面的代码来解码 json

$categories = json_decode($data);
$categories = $categories->data;

我在哪里得到这个

{"categories":[{"id":1,"name":"Utilities","apps":897,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/uti.jpg"},{"id":2,"name":"Productivity","apps":477,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/pro.jpg"},{"id":3,"name":"Music","apps":466,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/mus.jpg"},{"id":4,"name":"Travel","apps":289,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/tra.jpg"},{"id":5,"name":"Navigation","apps":297,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/nav.jpg"},{"id":6,"name":"Books","apps":271,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/boo.jpg"},{"id":7,"name":"Healthcare & Fitness","apps":250,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/hea.jpg"},{"id":8,"name":"Games","apps":5116,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/gam.jpg"},{"id":9,"name":"Social Networking","apps":272,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/soc.jpg"},{"id":10,"name":"Lifestyle","apps":434,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/lif.jpg"},{"id":11,"name":"Finance","apps":200,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/fin.jpg"},{"id":12,"name":"News","apps":128,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/new.jpg"},{"id":13,"name":"Photography","apps":481,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/pho.jpg"},{"id":14,"name":"Entertainment","apps":1251,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/ent.jpg"},{"id":15,"name":"Business","apps":221,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/bus.jpg"},{"id":16,"name":"Sports","apps":199,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/spo.jpg"},{"id":17,"name":"Education","apps":433,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/edu.jpg"},{"id":18,"name":"Medical","apps":262,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/med.jpg"},{"id":19,"name":"Weather","apps":64,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/wea.jpg"},{"id":20,"name":"Reference","apps":419,"iconurl":"http:\/\/static.apptrackr.org\/caticons\/ref.jpg"}]}

我想转换成这样的数组

Array[0]
    {
       id => 1
       name => Utilities
       apps => 897
       iconurl => http:\/\/static.apptrackr.org\/caticons\/uti.jpg
    }

等等

【问题讨论】：

标签： php arrays object

【解决方案1】：

这看起来像JSON string。您可以使用json_decode() 将其转换为 PHP 变量，例如

$obj = json_decode($json);
print_r($obj->categories); // array of StdClass objects

您可以定期访问和迭代类别数组

echo $obj->categories[0]->name; // Utilities
echo $obj->categories[1]->name; // Productivity
echo $obj->categories[2]->name; // Music

要将 StdClass 对象转换为数组，您可以这样做

$categories = array();
foreach (json_decode($json)->categories as $category) {
    $categories[] = (array) $category;
}
print_r($categories);

您也可以使用lambda function 和array_map：

// Before PHP5.3
$categories = array_map(
    create_function('$el', 'return (array) $el;'), 
    json_decode($json)->categories);

// After PHP5.3
$categories = array_map(
    function($el) { return (array) $el; }, 
    json_decode($json)->categories);

【讨论】：

很抱歉没有声明这个但为了得到这个我使用了 $categories = json_decode($data); $categories = $categories->数据；我在哪里得到了上面的结果，当我尝试使用你的代码时，我在 foreach 上遇到错误，感谢您的帮助
@Mahmoud 您提供的对象字符串中没有$categories->data。你得到什么错误？
这里是 print_r(json_decode($categories)); 的链接pastie.org/844979 我的问题是在我使用 $categories = $categories->data; 之后我在 foreach ($arr->categories as $category) { 中遇到的错误
@Mahmoud 我不确定你在那里做什么，但json_decode($categories) 和$categories 会源自你的$categories = json_decode($data); $categories = $categories->data; 工作吗？显然，您在data 中有一个包含 JSON 字符串的对象。
就像我说的，data 包含一个 JSON 字符串，您也需要解码才能将其转换为对象。见糊状。

【解决方案2】：

呃，你可以设置第二个参数来将 JSON 转换为数组而不是对象：

$categories = json_decode($data, true);

【讨论】：

【解决方案3】：

看看 get_object_vars http://php.net/manual/en/function.get-object-vars.php

【讨论】：

【解决方案4】：

@Gordon 似乎是正确的 - 看起来像 JSON。但是，假设您正在处理一个“实际的”PHP 对象，那么它将是可迭代的；只需使用foreach 运行它，然后将每个键/值对推送到您的目标数组中。

【讨论】：