Question

我正在尝试从数组项中向JSON添加元素，但我很难将元素传递给JSON。

这是我的代码：

var j = {
    "Root": {
        "a": "1800,1200,3100",
        "b": "1500,1999,2001",
        "c": "40,60,50",
        "d": "this is not needed",
        "e": "nor this one"
    }
};
var root = j.Root,
    l = root.a.split(",").length,
    hash = ["a", "b", "c"];


for (var i = 0; i < l; i++) {
    for (var x = 0; x < hash.length; x++) {
        root['row_' + i] = {
            "a": root.a.split(",")[i],
            "b": root.b.split(",")[i],
            "c": root.c.split(",")[i] // I don't want to do this for each key
        };
    }
}



for (var x = 0; x < hash.length; x++) {
    delete root[hash[x]];
}

console.log(JSON.stringify(j));

我的代码正在运行，但我正在寻找一种正确的方法来使用我的数组元素，因为我将拥有多个，b，c

PS：并非所有密钥都将被使用

Answer 1

您可以使用Object.keys来为hash变量中的对象提供密钥。然后，代码将动态检测Root对象中的所有可能键：

＆＃13;

var j = {
    "Root": {
        "a": "1800,1200,3100",
        "b": "1500,1999,2001",
        "c": "40,60,50",
        "d": "152,199,21",
        "e": "15,19,200"
    }
};
var root = j.Root,
    l = root.a.split(",").length,
    hash = ["a", "b", "c"];


for (var i = 0; i < l; i++) {
    var obj = {};
    for (var x = 0; x < hash.length; x++) {
        obj[hash[x]] = root[hash[x]].split(",")[i];
    }
    root['row_' + i] = obj;
}


for (var x = 0; x < hash.length; x++) {
    delete root[hash[x]];
}
console.log(root);
console.log(JSON.stringify(j));

＆＃13;

Answer 2

您可以迭代密钥并构建新属性。

＆＃13;

var object = { Root: { a: "1800,1200,3100", b: "1500,1999,2001", c: "40,60,50", d: "this is not needed", e: "nor this one" } },
    reference = object.Root;

Object
    .keys(reference)
    .forEach(k => {
        var values = reference[k].split(',');
        if (values.length === 1) {
            return;
        }
        values.forEach((v, i) => {
            reference['row_' + i] = reference['row_' + i] || {};
            reference['row_' + i][k] = v;
        });        
        delete reference[k];
    });

console.log(object);

＆＃13;

.as-console-wrapper { max-height: 100% !important; top: 0; }

＆＃13;

Answer 3

您可以使用以下方法获得所需的结果

reduce()
match()
Object.keys()
Object.values()

<强>样本

const root = {
    "Root": {
      "a": "1800,1200,3100",
      "b": "1500,1999,2001",
      "c": "40,60,50",
      "d": "this is not needed",
      "e": "nor this one"
    }
  },
  hash = ["a", "b", "c"],
  keys = Object.keys(root.Root);


let result = Object.values(root.Root).reduce((obj, value, index) => {
  if (value.match(',')) {
    value = value.split(',');
    obj[`row_${index}`] = hash.reduce((object, key, index) => {
      object[key] = value[index];
      return object;
    }, {});
  } else {
    obj[keys[index]] = value;
  }
  return obj;
}, {})

console.log(result);

从数组中添加json密钥

3 个答案: