PHP多维数组转JSON对象：新旧JSON结构匹配问题求助

PHP新手 [PHP 7.4]

正在重构旧代码，目标：两份JSON必须完全匹配，用PHPUnit做对比测试。

问题：新的动态生成代码输出的JSON比旧代码多了一组方括号；尝试用JSON_FORCE_OBJECT参数，虽移除了方括号，但引入了多余的数字键（如john下的"0"、marie下的"1"）。

旧代码（代码片段1） #

PHP数组代码 #

$body = [
    "data" => [
        "john" => [
            "byEmail" => [
                "status" => true,
                "source" => "my-server",
            ],
            "byPhoneCall" => [
                "status" => true,
                "source" => "my-server",
            ]
        ],
        "marie" => [
            "byEmail" => [
                "status" => true,
                "source" => "my-server",
            ],
            "byPhoneCall" => [
                "status" => true,
                "source" => "my-server",
            ]
        ]
    ]
];

执行json_encode()后的JSON结果 #

{
    "data": {
        "john": {
            "byEmail": {
                "source": "my-server",
                "status": true
            },
            "byPhoneCall": {
                "source": "my-server",
                "status": true
            }
        },
        "marie": {
            "byEmail": {
                "source": "my-server",
                "status": true
            },
            "byPhoneCall": {
                "source": "my-server",
                "status": true
            }
        }
    }
}

动态生成代码（代码片段2） #

为了支持未来新增字段（如johnByPost、johnByFax等），采用动态方式构建数组：

//my-file-dynamic-generation.php

public function constructArray($johnByEmail=null, $johnByPhone=null, $marieByEmail=null, $marieByPhone=null) {
    $body = [ "data" => ["john" => [], "marie" => []]];

    if ($johnByEmail !== null) {
        array_push($body["data"]["john"], $this->createKeyValuePair("byEmail", $johnByEmail));
    }

    if ($johnByPhone !== null) {
        array_push($body["data"]["john"], $this->createKeyValuePair("byPhoneCall", $johnByPhone));
    }

    if ($marieByEmail !== null) {
        array_push($body["data"]["marie"], $this->createKeyValuePair("byEmail", $marieByEmail));
    }

    if ($marieByPhone !== null) {
        array_push($body["data"]["marie"], $this->createKeyValuePair("byPhoneCall", $marieByPhone));
    }
    return $body;
}

// 辅助函数
function createKeyValuePair($title=null, $status=null, $source="my-server") {
    return [
        $title => [
            "status" => $status,
            "source" => $source,
        ]
    ];
}

问题根源 #

createKeyValuePair返回的是包含单个键值对的数组，再通过array_push将这些数组添加到john/marie的数组中，最终john变成了数组的数组（如[[byEmail: {...}], [byPhoneCall: {...}]]），json_encode后就会生成带方括号的JSON数组；而旧代码中john是关联数组，编码后是JSON对象（花括号）。

用JSON_FORCE_OBJECT会把数组强制转为对象，但会保留原数组的数字索引（0、1等），导致出现多余键。

解决方案 #

方案一：修改数组赋值方式，合并关联数组 #

不需要用array_push，而是将createKeyValuePair返回的数组直接合并到john/marie的关联数组中：

public function constructArray($johnByEmail=null, $johnByPhone=null, $marieByEmail=null, $marieByPhone=null) {
    $body = [ "data" => ["john" => [], "marie" => []]];

    if ($johnByEmail !== null) {
        $body["data"]["john"] = array_merge($body["data"]["john"], $this->createKeyValuePair("byEmail", $johnByEmail));
    }

    if ($johnByPhone !== null) {
        $body["data"]["john"] = array_merge($body["data"]["john"], $this->createKeyValuePair("byPhoneCall", $johnByPhone));
    }

    if ($marieByEmail !== null) {
        $body["data"]["marie"] = array_merge($body["data"]["marie"], $this->createKeyValuePair("byEmail", $marieByEmail));
    }

    if ($marieByPhone !== null) {
        $body["data"]["marie"] = array_merge($body["data"]["marie"], $this->createKeyValuePair("byPhoneCall", $marieByPhone));
    }
    return $body;
}

方案二：修改辅助函数，直接返回键值内容 #

让createKeyValuePair返回byEmail/byPhoneCall对应的内部数组，直接赋值给关联数组的键：

// 修改辅助函数
function createKeyValuePair($status=null, $source="my-server") {
    return [
        "status" => $status,
        "source" => $source,
    ];
}

// 修改constructArray方法
public function constructArray($johnByEmail=null, $johnByPhone=null, $marieByEmail=null, $marieByPhone=null) {
    $body = [ "data" => ["john" => [], "marie" => []]];

    if ($johnByEmail !== null) {
        $body["data"]["john"]["byEmail"] = $this->createKeyValuePair($johnByEmail);
    }

    if ($johnByPhone !== null) {
        $body["data"]["john"]["byPhoneCall"] = $this->createKeyValuePair($johnByPhone);
    }

    if ($marieByEmail !== null) {
        $body["data"]["marie"]["byEmail"] = $this->createKeyValuePair($marieByEmail);
    }

    if ($marieByPhone !== null) {
        $body["data"]["marie"]["byPhoneCall"] = $this->createKeyValuePair($marieByPhone);
    }
    return $body;
}

两种方案都能让john/marie成为正确的关联数组，json_encode后生成与旧代码完全一致的JSON对象，不会出现多余的方括号或数字键。

内容的提问来源于stack exchange，提问作者Rashedul