Question

我正在尝试运行for循环来创建新的javascript对象并添加到现有的javascript对象而不替换。

例如，我试图将此作为输出创建，而不是每次都覆盖组[i]（只添加数字[i]数据）：

{
    "group1": {
        "number1": "data",
        "number2": "data",
        "number3": "data"
    },
    "group2": {
        "number1": "data",
        "number2": "data"
    }
}

我的循环看起来像这样：

var array = [{
    "groupName": "group1",
    "number": "number1",
    "data": "data"
}, {
    "groupName": "group1",
    "number": "number2",
    "data": "data"
}, {
    "groupName": "group1",
    "number": "number3",
    "data": "data"
}, {
    "groupName": "group2",
    "number": "number1",
    "data": "data"
}, {
    "groupName": "group2",
    "number": "number2",
    "data": "data"
}]

var groupLinks = {};

for(i = 0; i < array.length; i++) {

    groupLinks[array[i].groupName] = { 
        [array[i].number]: array[i].data

}

正如您在此代码中所看到的，我的循环每次只会替换“group1”和“group2”。

Answer 1

这就是我接近这个的方法：

＆＃13;

var array = [{
    "groupName": "group1",
    "number": "number1",
    "data": "data"
}, {
    "groupName": "group1",
    "number": "number2",
    "data": "data"
}, {
    "groupName": "group1",
    "number": "number3",
    "data": "data"
}, {
    "groupName": "group2",
    "number": "number1",
    "data": "data"
}, {
    "groupName": "group2",
    "number": "number2",
    "data": "data"
}];

var groupLinks = {};

array.forEach(
    function (element)
    {
        var groupName = element.groupName;
        (groupLinks[groupName] = groupLinks[groupName] || {})
            [element.number] = element.data;

    }
);

console.log(groupLinks);

＆＃13;

这里我使用||运算符创建一个新组，当没有时，在每次迭代时覆盖现有的groupLinks[groupName]，并使用forEach构造循环数组元素

Answer 2

试试这个：

    var array = [{
        "groupName": "group1",
        "number": "number1",
        "data": "data"
    }, {
        "groupName": "group1",
        "number": "number2",
        "data": "data"
    }, {
        "groupName": "group1",
        "number": "number3",
        "data": "data"
    }, {
        "groupName": "group2",
        "number": "number1",
        "data": "data"
    }, {
        "groupName": "group2",
        "number": "number2",
        "data": "data"
    }]

    var groupLinks = {};

    array.forEach(function(el){
       if(groupLinks[el.groupName]){
         groupLinks[el.groupName][el.number] = el.data
       }
       else{
         groupLinks[el.groupName] = {};
         groupLinks[el.groupName][el.number] = el.data
       }

    });

   console.log(groupLinks);

Answer 3

如果您不害怕ES2015，那么减少工作应该适合您

＆＃13;

let array = [{"groupName":"group1","number":"number1","data":"data"},{"groupName":"group1","number":"number2","data":"data"},{"groupName":"group1","number":"number3","data":"data"},{"groupName":"group2","number":"number1","data":"data"},{"groupName":"group2","number":"number2","data":"data"}];

let groupLinks = array.reduce((gl, group) => {
    gl[group.groupName] = Object.assign({
        [group.number]: group.data
    }, gl[group.groupName]);
    return gl;
}, Object.create(null));

console.log(groupLinks);

＆＃13;

Answer 4

请试试这个：

    var groupLinks = {};

    for(i = 0; i < array.length; i++) {
       var groupLinks2 = groupLinks[array[i].groupName];
       if(!groupLinks2){
           groupLinks2 ={};
           var a = array[i].number;
           groupLinks2[a] = array[i].data;
      }else{
         var a = array[i].number;
        groupLinks2[a] = array[i].data;
      }
      groupLinks[array[i].groupName] = groupLinks2;

   }

在不替换子项的情况下添加到Javascript对象

4 个答案: