使用 PHP 解析和回显 JSON

Question

好吧，我在过去的 24 小时里都撞到了头，在测试和阅读 SO 之后无法弄清楚这一点。我有一个需要解析的 JSON 文件，由于某种原因，我无法获得正确的代码组合来回显除“数组”或“尝试获取非对象的属性”或“为 foreach 提供的参数无效”之外的任何内容（ )”。这是我试图迭代的完整 JSON。我需要打印出每个“项目”的名称、每个项目中的“数据集”以及每个“数据集”的“权限”。我正在自己构建这个 JSON，所以我可以在必要时更改格式。

$data = json_decode($json, true);

在下面输出 JSON：

[
   [
      {
         "projects":[
            {
               "project":"test-project-1",
               "datasets":[
                  {
                     "dataset":"testing1",
                     "permissions":[
                        {
                           "role":"READER",
                           "google_group":"testing1@test.com"
                        }
                     ]
                  },
                  {
                     "dataset":"testing2",
                     "permissions":[
                        {
                           "role":"OWNER",
                           "google_group":"testing2@test.com"
                        }
                     ]
                  },
                  {
                     "dataset":"testing3",
                     "permissions":[
                        {
                           "role":"READER",
                           "google_group":"testing3@test.com"
                        }
                     ]
                  },
                  {
                     "dataset":"testing4",
                     "permissions":[
                        {
                           "role":"WRITER",
                           "google_group":"testing4@test.com"
                        }
                     ]
                  }
               ]
            },
            {
               "project":"test-project-2",
               "datasets":[
                  {
                     "dataset":"testing1",
                     "permissions":[
                        {
                           "role":"READER",
                           "google_group":"testing1@test.com"
                        }
                     ]
                  },
                  {
                     "dataset":"testing2",
                     "permissions":[
                        {
                           "role":"READER",
                           "google_group":"testing2@test.com"
                        }
                     ]
                  },
                  {
                     "dataset":"testing3",
                     "permissions":[
                        {
                           "role":"READER",
                           "google_group":"testing3@test.com"
                        }
                     ]
                  },
                  {
                     "dataset":"testing4",
                     "permissions":[
                        {
                           "role":"READER",
                           "google_group":"testing4@test.com"
                        }
                     ]
                  }
               ]
            }
         ]
      }
   ]
]

我尝试过类似的方法：

foreach($data->projects as $output)
{
    echo $output->project . "\n";
    foreach($output->datasets as $datasets)
    {
        echo $output->dataset . "\n";
    }
}

感谢您的帮助！

编辑：解析上述 JSON 的工作代码：

$projects = $json['projects'];
foreach ($projects as $project) {
    echo $project['project'] . "<br>";
    foreach ($json['projects'][0]['datasets'] as $datasets){
        echo $datasets['dataset'] . "<br>";
        foreach ($json['projects'][0]['datasets'][0]['permissions'] as $permissions){
            echo $permissions['role'] . "<br>";
            echo $permissions['google_group'] . "<br>";
        }
    }
}

Answer 1

您的 json 包含两个嵌套数组，其中包含您想要的对象。所以首先你可以使用[0][0] 之类的东西来获取包含项目的关联数组。

// ...
$projects = $json['projects'];
foreach ($projects as $project) {
    echo "Project: " . $project['project'] . "\n";
    foreach ($project['datasets'] as $dataset) {
        echo "Dataset: " . $dataset['dataset'];
        foreach ($dataset['permissions'][0] as $key => $value) {
            // ...
        }
    }
}