我已经多次解析JSON数据，但是由于某种原因，无法找到嵌套数据时要使用的正确语法。我正在尝试从此JSON解析“资产”，但是无论我尝试什么，都继续获取为foreach（）提供的无效参数。

   "3435":{
      "name":"COLO-1014-SJ1",
      "nickname":"US-SJC-004",
      "type":"Colocated Server",
      "location":"San Jose:55 S Market",
      "assets":{
         "CPU":[
            {
               "model":"Intel E3 1270"
            }
         ],
         "Hard Drives":[
            {
               "model":"Western Digital 500GB RE4 ABYX SATA"
            },
            {
               "model":"Western Digital 500GB RE4 ABYX SATA"
            },
            {
               "model":"Kingston 240GB SSD"
            }
         ],
         "RAM":[
            {
               "model":"Super Talent 4GB DDR3 1333 ECC"
            },
            {
               "model":"Super Talent 4GB DDR3 1333 ECC"
            },
            {
               "model":"Super Talent 4GB DDR3 1333 ECC"
            },
            {
               "model":"Super Talent 4GB DDR3 1333 ECC"
            }
         ],

我希望这是…

$json = json_decode($jsondata, true);

foreach ($json as $item)
{
    foreach ($item['assets']->RAM as $asset)
    {
        echo $asset->model;
    }