javascript - オブジェクト キーの名前を再帰的に変更する

Question

オブジェクトのキー名の名前を変更する再帰関数がありますが、2 つのキーの名前を変更する方法がわかりません (問題のキーはオブジェクトです)。

問題はオブジェクトの種類をチェックしているところだと思いますが、その時点でキーの名前を変更するにはどうすればよいですか?

実際の配列は非常に大きいですが、縮小版を以下に示します。

どんな助けでも感謝します。

var keys_short = ['ch','d','u','tz'];
var keys_long = ['children','data','user_id','time_zone'];
function refit_keys(o){
    build = {};
    for (var i in o){
        if(typeof(o[i])=="object"){
            o[i] = refit_keys(o[i]);
            build = o;
        }else{
            var ix = keys_short.indexOf(i);
            if(ix!=-1){
                build[keys_long[ix]] = o[keys_short[ix]];
            }
        }
    }
    return build;
}

私の入力は次のようになります。

{
    "id":"1",
    "ch":[
        {
            "id":"3",
            "ch":[
            ],
            "d":{
                "u":"3",
                "tz":"8.00"
            }
        },
        {
            "id":"45",
            "ch":[
                {
                    "id":"70",
                    "ch":[
                        {
                            "id":"43",
                            "ch":[
                            ],
                            "d":{
                                "u":"43",
                                "tz":"-7.00"
                            }
                        }
                    ],
                    "d":{
                        "u":"70",
                        "tz":"-7.00"
                    }
                }
            ],
            "d":{
                "u":"45",
                "tz":"-7.00"
            }
        }
    ],
    "d":{
        "u":"1",
        "tz":"8.00"
    }
}

このような私の出力：

{
    "id":"1",
    "ch":[
        {
            "id":"3",
            "ch":[
            ],
            "d":{
                "user_id":"3",
                "time_zone":"8.00"
            }
        },
        {
            "id":"45",
            "ch":[
                {
                    "id":"70",
                    "ch":[
                        {
                            "id":"43",
                            "ch":[
                            ],
                            "d":{
                                "user_id":"43",
                                "time_zone":"-7.00"
                            }
                        }
                    ],
                    "d":{
                        "user_id":"70",
                        "time_zone":"-7.00"
                    }
                }
            ],
            "d":{
                "user_id":"45",
                "time_zone":"-7.00"
            }
        }
    ],
    "d":{
        "user_id":"1",
        "time_zone":"8.00"
    }
}

Answer 1

そこにはいくつかの問題があります。

1 つは、関数内で変数を宣言しないことで、暗黙的グローバルの恐怖の餌食になっていることです。build

ただし、ロジックにも問題があります。最小限の再加工を次に示します。

var keys_short = ["ch","d","u","tz"];
var keys_long = ["children","data","user_id","time_zone"];
function refit_keys(o){
    var build, key, destKey, ix, value;

    // Only handle non-null objects
    if (o === null || typeof o !== "object") {
        return o;
    }

    // Handle array just by handling their contents
    if (Array.isArray(o)) {
        return o.map(refit_keys);
    }

    // We have a non-array object
    build = {};
    for (key in o) {
        // Get the destination key
        ix = keys_short.indexOf(key);
        destKey = ix === -1 ? key : keys_long[ix];

        // Get the value
        value = o[key];

        // If this is an object, recurse
        if (typeof value === "object") {
            value = refit_keys(value);
        }

        // Set it on the result using the destination key
        build[destKey] = value;
    }
    return build;
}

実際の例:

"use strict";
var input = {
    "id":"1",
    "ch":[
        {
            "id":"3",
            "ch":[
            ],
            "d":{
                "u":"3",
                "tz":"8.00"
            }
        },
        {
            "id":"45",
            "ch":[
                {
                    "id":"70",
                    "ch":[
                        {
                            "id":"43",
                            "ch":[
                            ],
                            "d":{
                                "u":"43",
                                "tz":"-7.00"
                            }
                        }
                    ],
                    "d":{
                        "u":"70",
                        "tz":"-7.00"
                    }
                }
            ],
            "d":{
                "u":"45",
                "tz":"-7.00"
            }
        }
    ],
    "d":{
        "u":"1",
        "tz":"8.00"
    }
};

var keys_short = ["ch","d","u","tz"];
var keys_long = ["children","data","user_id","time_zone"];
function refit_keys(o){
    var build, key, destKey, ix, value;

    // Only handle non-null objects
    if (o === null || typeof o !== "object") {
        return o;
    }

    // Handle array just by handling their contents
    if (Array.isArray(o)) {
        return o.map(refit_keys);
    }

    // We have a non-array object
    build = {};
    for (key in o) {
        // Get the destination key
        ix = keys_short.indexOf(key);
        destKey = ix === -1 ? key : keys_long[ix];

        // Get the value
        value = o[key];

        // If this is an object, recurse
        if (typeof value === "object") {
            value = refit_keys(value);
        }

        // Set it on the result using the destination key
        build[destKey] = value;
    }
    return build;
}

console.log(refit_keys(input));

.as-console-wrapper {
    max-height: 100% !important;
}

ただし、並列配列ではなく、オブジェクトまたはMap:を介してマッピングを使用することをお勧めします。

// Object with no prototype to avoid false matches on `toString` and other built-ins
var mapShortToLong = Object.assign(Object.create(null), {
    "ch": "children",
    "d":  "data",
    "u":  "user_id",
    "tz": "time_zone"
});
function refit_keys(o){
    var build, key, destKey, value;

    // Only handle non-null objects
    if (o === null || typeof o !== "object") {
        return o;
    }

    // Handle array just by handling their contents
    if (Array.isArray(o)) {
        return o.map(refit_keys);
    }

    build = {};
    for (key in o) {
        // Get the destination key
        destKey = mapShortToLong[key] || key;

        // Get the value
        value = o[key];

        // If this is an object, recurse
        if (typeof value === "object") {
            value = refit_keys(value);
        }

        // Set it on the result using the destination key
        build[destKey] = value;
    }
    return build;
}

実際の例:

"use strict";
var input = {
    "id":"1",
    "ch":[
        {
            "id":"3",
            "ch":[
            ],
            "d":{
                "u":"3",
                "tz":"8.00"
            }
        },
        {
            "id":"45",
            "ch":[
                {
                    "id":"70",
                    "ch":[
                        {
                            "id":"43",
                            "ch":[
                            ],
                            "d":{
                                "u":"43",
                                "tz":"-7.00"
                            }
                        }
                    ],
                    "d":{
                        "u":"70",
                        "tz":"-7.00"
                    }
                }
            ],
            "d":{
                "u":"45",
                "tz":"-7.00"
            }
        }
    ],
    "d":{
        "u":"1",
        "tz":"8.00"
    }
};

// Object with no prototype to avoid false matches on `toString` and other built-ins
var mapShortToLong = Object.assign(Object.create(null), {
    "ch": "children",
    "d":  "data",
    "u":  "user_id",
    "tz": "time_zone"
});
function refit_keys(o){
    var build, key, destKey, value;

    // Only handle non-null objects
    if (o === null || typeof o !== "object") {
        return o;
    }

    // Handle array just by handling their contents
    if (Array.isArray(o)) {
        return o.map(refit_keys);
    }

    build = {};
    for (key in o) {
        // Get the destination key
        destKey = mapShortToLong[key] || key;

        // Get the value
        value = o[key];

        // If this is an object, recurse
        if (typeof value === "object") {
            value = refit_keys(value);
        }

        // Set it on the result using the destination key
        build[destKey] = value;
    }
    return build;
}

console.log(refit_keys(input));

.as-console-wrapper {
    max-height: 100% !important;
}

または最新の JavaScript では:

// Using a `Map` here to provide a `Map` example, but you can ue an object as
// in the previous ones if you prefer if the keys are strings
const mapShortToLong = new Map([
    ["ch", "children"],
    ["d",  "data"],
    ["u",  "user_id"],
    ["tz", "time_zone"],
]);
function refit_keys(o){
    // Only handle non-null objects
    if (o === null || typeof o !== "object") {
        return o;
    }

    // Handle array just by handling their contents
    if (Array.isArray(o)) {
        return o.map(refit_keys);
    }

    const build = {};
    for (const key in o) {
        // Get the destination key
        const destKey = mapShortToLong.get(key) || key;

        // Get the value
        let value = o[key];

        // If this is an object, recurse
        if (typeof value === "object") {
            value = refit_keys(value);
        }

        // Set it on the result using the destination key
        build[destKey] = value;
    }
    return build;
}

実際の例:

"use strict";
var input = {
    "id":"1",
    "ch":[
        {
            "id":"3",
            "ch":[
            ],
            "d":{
                "u":"3",
                "tz":"8.00"
            }
        },
        {
            "id":"45",
            "ch":[
                {
                    "id":"70",
                    "ch":[
                        {
                            "id":"43",
                            "ch":[
                            ],
                            "d":{
                                "u":"43",
                                "tz":"-7.00"
                            }
                        }
                    ],
                    "d":{
                        "u":"70",
                        "tz":"-7.00"
                    }
                }
            ],
            "d":{
                "u":"45",
                "tz":"-7.00"
            }
        }
    ],
    "d":{
        "u":"1",
        "tz":"8.00"
    }
};

// Using a `Map` here to provide a `Map` example, but you can ue an object as
// in the previous ones if you prefer if the keys are strings
const mapShortToLong = new Map([
    ["ch", "children"],
    ["d",  "data"],
    ["u",  "user_id"],
    ["tz", "time_zone"],
]);
function refit_keys(o){
    // Only handle non-null objects
    if (o === null || typeof o !== "object") {
        return o;
    }

    // Handle array just by handling their contents
    if (Array.isArray(o)) {
        return o.map(refit_keys);
    }

    const build = {};
    for (const key in o) {
        // Get the destination key
        const destKey = mapShortToLong.get(key) || key;

        // Get the value
        let value = o[key];

        // If this is an object, recurse
        if (typeof value === "object") {
            value = refit_keys(value);
        }

        // Set it on the result using the destination key
        build[destKey] = value;
    }
    return build;
}

console.log(refit_keys(input));

.as-console-wrapper {
    max-height: 100% !important;
}

Answer 2

build問題の 1 つは、変数が実際にはグローバル変数である可能性があります。したがって、再帰の最初の深さの結果のみが含まれます。

varbeforeを追加するbuildと、問題の一部が解決するはずです。