json_decode

json_encode([])

json_encode(new stdClass())

{}

$data['level1']['level2']['field']

<?php
$complexJson = '{
    "user": {
        "profile": {
            "name": "張三",
            "contact": {
                "email": "zhangsan@example.com",
                "phone": null
            }
        },
        "preferences": null
    }
}';

$data = json_decode($complexJson, true);

// 安全獲取數(shù)據(jù)，避免Undefined index警告
$userName = $data['user']['profile']['name'] ?? '未知用戶';
echo "用戶名: " . $userName . "\n";

$userPhone = $data['user']['profile']['contact']['phone'] ?? '未提供電話';
echo "電話: " . $userPhone . "\n";

// 如果preferences可能不存在或?yàn)閚ull
$userPreferences = $data['user']['preferences'] ?? []; // 默認(rèn)為空數(shù)組
var_dump($userPreferences);
?>

justinrainbow/json-schema

// 假設(shè)你已經(jīng)通過(guò) Composer 安裝了 justinrainbow/json-schema
// composer require justinrainbow/json-schema

// 示例代碼（僅為概念展示，需完整配置和錯(cuò)誤處理）
use JsonSchema\Validator;
use JsonSchema\Constraints\Constraint;

$data = json_decode($complexJson); // 注意這里解碼為對(duì)象，因?yàn)閖son-schema庫(kù)通常期望對(duì)象
$schema = json_decode('{
    "type": "object",
    "properties": {
        "user": {
            "type": "object",
            "properties": {
                "profile": {
                    "type": "object",
                    "properties": {
                        "name": {"type": "string"},
                        "contact": {
                            "type": "object",
                            "properties": {
                                "email": {"type": "string", "format": "email"},
                                "phone": {"type": ["string", "null"]}
                            },
                            "required": ["email"]
                        }
                    },
                    "required": ["name", "contact"]
                }
            },
            "required": ["profile"]
        }
    },
    "required": ["user"]
}');

$validator = new Validator;
$validator->validate($data, $schema);

if ($validator->isValid()) {
    echo "JSON數(shù)據(jù)驗(yàn)證通過(guò)！\n";
} else {
    echo "JSON數(shù)據(jù)驗(yàn)證失敗。錯(cuò)誤列表:\n";
    foreach ($validator->getErrors() as $error) {
        echo sprintf("[%s] %s\n", $error['property'], $error['message']);
    }
}

halite/json-stream

salsify/jsonstream

// 偽代碼，展示流式解析概念
// 假設(shè)你使用了一個(gè)流式解析庫(kù)
// use SomeStreamJsonParser;

// $parser = new SomeStreamJsonParser('path/to/large_data.json');
// foreach ($parser->parse() as $item) {
//     // 逐個(gè)處理JSON中的對(duì)象或數(shù)組元素
//     // 內(nèi)存占用小
//     processItem($item);
// }