Lodash 选择嵌套键答案

【问题标题】：Lodash pick nested keyLodash 选择嵌套键
【发布时间】：2021-09-18 17:34:13
【问题描述】：

我有以下对象：

{
    "coins": [],
    "contract": "terra1u0t35drzyy0mujj8rkdyzhe264uls4ug3wdp3x",
    "execute_msg": {
        "send": {
            "amount": "1000000",
            "contract": "terra1ltnkx0mv7lf2rca9f8w740ashu93ujughy4s7p",
            "msg": "eyJkZXBvc2l0X2NvbGxhdGVyYWwiOnt9fQ=="
        }
    },
    "sender": "terra194rswjxvv0a2fm3f8hr4e4f3443dl3s7frsyhp"
}


{
    "amount": [
        {
            "amount": "1000000",
            "denom": "uusd"
        }
    ],
    "from_address": "terra194rswjxvv0a2fm3f8hr4e4f3443dl3s7frsyhp",
    "to_address": "terra1ux73wdfgmu7r5us2sf0u9vdmrfxuhdk8760zzj"
}

{
    "coins": [
        {
            "amount": "2000000",
            "denom": "uusd"
        }
    ],
    "contract": "terra15dwd5mj8v59wpj0wvt233mf5efdff808c5tkal",
    "execute_msg": {
        "deposit_stable": {}
    },
    "sender": "terra194rswjxvv0a2fm3f8hr4e4f3443dl3s7frsyhp"
}

我想从每个对象中提取数量键并使用 lodash 选择该键对应的数字。我已经尝试过“findKey”和“pick”运算符，但我认为不要正确使用它们，并且知道如何获得最嵌套的数量键

【问题讨论】：

标签： javascript lodash

【解决方案1】：

您可以使用实现的mixin here 获得所有对象对的扁平化版本。

之后，使用Map 存储它们并获取amount 的值：

_.mixin({
  toPairsDeep: obj => _.flatMap(
    _.toPairs(obj), 
    ([k, v]) => _.isObjectLike(v) ? _.toPairsDeep(v) : [[k, v]]
  )
});

const getAmount = obj => new Map(_.toPairsDeep(obj)).get("amount");

console.log( getAmount({ "coins": [], "contract": "terra1u0t35drzyy0mujj8rkdyzhe264uls4ug3wdp3x", "execute_msg": { "send": { "amount": "1000000", "contract": "terra1ltnkx0mv7lf2rca9f8w740ashu93ujughy4s7p", "msg": "eyJkZXBvc2l0X2NvbGxhdGVyYWwiOnt9fQ==" } }, "sender": "terra194rswjxvv0a2fm3f8hr4e4f3443dl3s7frsyhp" }) );
console.log( getAmount({ "amount": [ { "amount": "1000000", "denom": "uusd" } ], "from_address": "terra194rswjxvv0a2fm3f8hr4e4f3443dl3s7frsyhp", "to_address": "terra1ux73wdfgmu7r5us2sf0u9vdmrfxuhdk8760zzj" }) );
console.log( getAmount({ "coins": [ { "amount": "2000000", "denom": "uusd" } ], "contract": "terra15dwd5mj8v59wpj0wvt233mf5efdff808c5tkal", "execute_msg": { "deposit_stable": {} }, "sender": "terra194rswjxvv0a2fm3f8hr4e4f3443dl3s7frsyhp" }) );

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【讨论】：