Question

如果值匹配，我想将值从一个数组插入到另一个数组。

这些是我的数组。

var names = [{key: 'Apple'}, {key: 'Dell'}, {key: 'Xitrix'}];
var data = [
     {enum_name:'Apple', date:'2000-12-15', accomp: 12},
     {enum_name:'Dell', date:'2000-12-15', accomp: 8},
     {enum_name:'Apple', date:'2000-12-16', accomp: 12},
     {enum_name:'Xitrix', date:'2000-12-16', accomp: 12},
     {enum_name:'Dell', date:'2000-12-17', accomp: 8},
     {enum_name:'Xitrix', date:'2000-12-17', accomp: 12},
];

然后我想使用特定键（例如attrib：[arrays];

）将data.date和data.accomp插入数组名称

我有这段代码，但是它没有将所有匹配的数据插入键 attrib 。

    var counts = 0;
    _.each(names, function(v, k){
        _.each(data, function(val, key){
            if(v.key == val.enum_name){
                var date = val.date;
                var accomp= val.accomp;

                names[k].attrib= [[date, accomp]];
                console.log(counts);
                counts++;
            }
        });
        counts = 0;
        //names[k]['values'] = 'test';
    });

我想要这样的输出。

 names = [
    {key: 'Apple', attrib: [['2000-12-15', 12], ['2000-12-16', 12]]}, 
    {key: 'Dell', attrib: [['2000-12-15', 8], ['2000-12-17', 8]]},
    {key: 'Xitrix', attrib: [['2000-12-16', 12], ['2000-12-17', 12]]}
 ];

Answer 1

尝试将reduce用于由enum_name索引并带有date和accomp数组的对象，然后获取该对象的值，不需要库，并且运行时复杂度更低：

var names = [{key: 'Apple'}, {key: 'Dell'}, {key: 'Xitrix'}];
var data = [
   {enum_name:'Apple', date:'2000-12-15', accomp: 12},
   {enum_name:'Dell', date:'2000-12-15', accomp: 8},
   {enum_name:'Apple', date:'2000-12-16', accomp: 12},
   {enum_name:'Xitrix', date:'2000-12-16', accomp: 12},
   {enum_name:'Dell', date:'2000-12-17', accomp: 8},
   {enum_name:'Xitrix', date:'2000-12-17', accomp: 12},
];
console.log(Object.values(
  data.reduce((a, { enum_name: key, date, accomp }) => {
    if (!a[key]) a[key] = { key, attrib: [] };
    a[key].attrib.push([date, accomp]);
    return a;
  }, {})
));

Answer 2

首先，创建一个包含names元素的对象，并以key属性为键，因此很容易找到特定键的元素，然后将attrib属性添加到他们。

Lodash：

var namesObj = _.forEach(_.keyBy(names, 'key'), n => n.attrib = []);

Undercore.js：

var namesObject = _.each(_.indexBy(names, 'key'), n => n.attrib = []);

然后，您可以遍历数据并将属性推送到适当的对象上。

_.each(data, ({enum_name, date, accomp}) => 
    namesObj[enum_name].attribs.push([date, accomp])
);

Answer 3

Underscore where filter

Plz尝试输入以下代码：[]

  var names = [{ key: 'Apple' }, { key: 'Dell' }, { key: 'Xitrix' }];
  var data = [
    { enum_name: 'Apple', date: '2000-12-15', accomp: 12 },
    { enum_name: 'Dell', date: '2000-12-15', accomp: 8 },
    { enum_name: 'Apple', date: '2000-12-16', accomp: 12 },
    { enum_name: 'Xitrix', date: '2000-12-16', accomp: 12 },
    { enum_name: 'Dell', date: '2000-12-17', accomp: 8 },
    { enum_name: 'Xitrix', date: '2000-12-17', accomp: 12 }
  ];
  // new array
  var new_data = [];
  // loop names
  _.each(names, function (v) {
    // init new obj
    var obj = { key: v.key, attrib: [] };
    // find by underscore with key of names & enum_name of data
    var finds = _.where(data, { enum_name: v.key });
    // if using lodash then change to _.find:
    // var finds = _.find(data, { enum_name: v.key });
    // loop finds
    _.each(finds, function (value) {
      // add attrib
      obj.attrib.push([value.date, value.accomp]);
    });
    // add obj to new array
    new_data.push(obj);
  });
  console.log(new_data);

如何在javascript中将值插入数组

3 个答案: