如何将JSON字符串转换为数组（PHP）？

Question

使用用于解码JSON下面的代码

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

其中i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"}]} 

，我想转换成在一个阵列这样

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

等

Answer 1

这看起来像是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 

您可以访问和迭代的类别阵列定期

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

到了一个StdClass对象转换为数组，你可以做

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

你也可以用lambda function并做到这一点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); 

Answer 2

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

Answer 3

@戈登似乎是正确的 - 那看起来像JSON。假设你正在处理一个“实际的”PHP对象，那么它将是可迭代的;只需用foreach运行它并将每个键/值对推入目标阵列。

Answer 4

呃，你可以设置第二个参数，以JSON转换成一个数组，而不是插入的对象：

$categories = json_decode($data, true);