PHPJSON怎么处理_PHPJSON数据编码与解码方法详解

<?php
// 示例1: 编码一个关联数组
$data = [
    'name' => '张三',
    'age' => 30,
    'isStudent' => false,
    'courses' => ['数学', '英语', '计算机'],
    'address' => null
];
$jsonString = json_encode($data);
echo $jsonString;
// 输出: {"name":"\u5f20\u4e09","age":30,"isStudent":false,"courses":["\u6570\u5b66","\u82f1\u8bed","\u8ba1\u7b97\u673a"],"address":null}
echo "\n";

// 示例2: 使用JSON_UNESCAPED_UNICODE选项避免中文乱码，并使用JSON_PRETTY_PRINT美化输出
$jsonStringPretty = json_encode($data, JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT);
echo $jsonStringPretty;
/* 输出:
{
    "name": "张三",
    "age": 30,
    "isStudent": false,
    "courses": [
        "数学",
        "英语",
        "计算机"
    ],
    "address": null
}
*/
echo "\n";

// 示例3: 编码一个对象
class User {
    public $id;
    public $username;
    private $password; // 私有属性默认不会被编码

    public function __construct($id, $username, $password) {
        $this->id = $id;
        $this->username = $username;
        $this->password = $password;
    }
}
$user = new User(1, 'lisi', 'secret');
$jsonUser = json_encode($user, JSON_UNESCAPED_UNICODE);
echo $jsonUser;
// 输出: {"id":1,"username":"lisi"}
echo "\n";

// 示例4: 检查编码错误
$invalidData = "\xB1\x31"; // 非UTF-8字符串
$jsonInvalid = json_encode($invalidData);
if ($jsonInvalid === false) {
    echo "JSON编码失败: " . json_last_error_msg() . "\n";
}
?>

<?php
// 示例1: 解码为PHP对象
$jsonString = '{"name":"张三","age":30,"isStudent":false,"courses":["数学","英语","计算机"],"address":null}';
$phpObject = json_decode($jsonString);
print_r($phpObject);
/* 输出:
stdClass Object
(
    [name] => 张三
    [age] => 30
    [isStudent] =>
    [courses] => Array
        (
            [0] => 数学
            [1] => 英语
            [2] => 计算机
        )
    [address] =>
)
*/
echo "\n";

// 示例2: 解码为关联数组
$phpArray = json_decode($jsonString, true); // 第二个参数设为true
print_r($phpArray);
/* 输出:
Array
(
    [name] => 张三
    [age] => 30
    [isStudent] =>
    [courses] => Array
        (
            [0] => 数学
            [1] => 英语
            [2] => 计算机
        )
    [address] =>
)
*/
echo "\n";

// 示例3: 处理无效JSON
$invalidJson = '{"name":"张三", "age":30,'; // 缺少闭合括号
$result = json_decode($invalidJson);
if ($result === null && json_last_error() !== JSON_ERROR_NONE) {
    echo "JSON解码失败: " . json_last_error_msg() . "\n";
}
?>

<?php
// 检查json_encode错误
$bad_string = iconv('UTF-8', 'GBK', '你好'); // 模拟非UTF-8字符串
$encoded = json_encode($bad_string);
if ($encoded === false) {
    echo "编码错误：" . json_last_error_msg() . "\n"; // 输出：编码错误：Malformed UTF-8 characters, possibly incorrectly encoded
}

// 检查json_decode错误
$malformed_json = '{"key": "value",}'; // 尾部多余逗号
$decoded = json_decode($malformed_json);
if ($decoded === null && json_last_error() !== JSON_ERROR_NONE) {
    echo "解码错误：" . json_last_error_msg() . "\n"; // 输出：解码错误：Syntax error
}

$valid_null_json = 'null';
$decoded_null = json_decode($valid_null_json);
if ($decoded_null === null && json_last_error() === JSON_ERROR_NONE) {
    echo "这是一个合法的JSON null值，被解码为PHP的null。\n";
}
?>

<?php
$complexJson = '{
    "orderId": "ORD20230815001",
    "customer": {
        "id": 101,
        "name": "李四",
        "contact": {
            "email": "lisi@example.com",
            "phone": ["13800138000", "010-12345678"]
        }
    },
    "items": [
        {
            "itemId": "ITEM001",
            "name": "商品A",
            "price": 100.50,
            "quantity": 2,
            "tags": ["电子产品", "热销"]
        },
        {
            "itemId": "ITEM002",
            "name": "商品B",
            "price": 50.00,
            "quantity": 1
        }
    ],
    "status": "pending"
}';

// 解码为关联数组
$data = json_decode($complexJson, true);

if ($data === null && json_last_error() !== JSON_ERROR_NONE) {
    echo "解码复杂JSON失败: " . json_last_error_msg() . "\n";
} else {
    echo "订单ID: " . $data['orderId'] . "\n";
    echo "客户姓名: " . $data['customer']['name'] . "\n";
    echo "客户邮箱: " . $data['customer']['contact']['email'] . "\n";
    echo "客户电话1: " . $data['customer']['contact']['phone'][0] . "\n";

    echo "订单商品列表:\n";
    foreach ($data['items'] as $item) {
        echo "  - " . $item['name'] . " (数量: " . $item['quantity'] . ", 价格: " . $item['price'] . ")\n";
        if (isset($item['tags'])) {
            echo "    标签: " . implode(', ', $item['tags']) . "\n";
        }
    }
}

// 如果解码为对象
$objData = json_decode($complexJson);
if ($objData !== null) {
    echo "\n通过对象访问:\n";
    echo "订单ID: " . $objData->orderId . "\n";
    echo "客户姓名: " . $objData->customer->name . "\n";
    echo "客户电话2: " . $objData->customer->contact->phone[1] . "\n";
}
?>