使用 objects/arrays 中的 PHP 从文件中解析 JSON

Question

我使用 print_r in php 解码后的 JSON 获得以下输出：

stdClass Object
(
    [assignments] => Array
        (
            [0] => stdClass Object
                (
                    [assignmentid] => 1
                    [grades] => Array
                        (
                            [0] => stdClass Object
                                (
                                    [id] => 1
                                    [userid] => 3
                                    [attemptnumber] => 0
                                    [timecreated] => 1484244192
                                    [timemodified] => 1484244203
                                    [grader] => 2
                                    [grade] => 85.00000
                                )

                        )

                )

        )

    [warnings] => Array
        (
        )

)

我想获取 [grade] => 85.00000 的值并将其存储在变量中。我该怎么做？

Answer 1

怎么样：

$var = $obj->assignments[0]->grades[0]->grade;

Answer 2

使用 true 作为 json_decode() 的第二个参数将其解码为数组，然后您必须循环遍历结果。

$data = json_decode($json, true);
foreach ($data['assignments'] as $row) { 
    foreach ($row['grades'] as $grade) {
        echo $grade['grade'];
    }
}