Question

我想使用给定的记录创建数组的数组。

user_permission =
 [ { _id: 1,
    description: 'chairman list',
    main_module: 'admin',
    sub_module: 'admin' },
  { _id: 2,
    description: 'create chairman get method',
    main_module: 'admin',
    sub_module: 'admin' },
  { _id: 3,
    description: 'create chairman post method',
    main_module: 'admin',
    sub_module: 'admin' },
  { _id: 4,
    description: 'chairman list post',
    main_module: 'chairman',
    sub_module: 'chairman' },
  { _id: 5,
    description: 'vendor list',
    main_module: 'vendor',
    sub_module: 'vendor' },
  { _id: 6,
    description: 'vendor list post',
    main_module: 'vendor',
    sub_module: 'vendor' } ]

使用此数组，我想像给定示例一样生成这种类型的数组

[ 
    [ 'admin > admin': { '1': 'chairman list' },
                       { '2': 'create chairman get method' },
                       { '3': 'create chairman post method' } 
    ],
    [ 'chairman > chairman': { '4': 'chairman list post' } 
    ],
    [ 'vendor > vendor': { '5': 'vendor list' },
                         { '6': 'vendor list post' } 
    ] 
]

使用foreach并获取结果，但是我没有创建适当的数组

user_permission.forEach(function(data){
    var mainmodule = [[data.main_module]+" > "+[data.sub_module]];
    var key = data._id;
    var val = data.description;

    var elem = new Array();
    elem[mainmodule] ={};
    elem[mainmodule][key] = val;
    user_prems.push(elem);
})

foreach的结果如下：-

[ 
    [ 'admin > admin': { '1': 'chairman list' } ],
    [ 'admin > admin': { '2': 'create chairman get method' } ],
    [ 'admin > admin': { '3': 'create chairman post method' } ],
    [ 'chairman > chairman': { '4': 'chairman list post' } ],
    [ 'vendor > vendor': { '5': 'vendor list' } ],
    [ 'vendor > vendor': { '6': 'vendor list post' } ] 
]

Answer 1

首先，您的预期输出不正确。您应该有一个对象而不是数组。并且他们使用reduce()来获得一个对象，该对象的键为admin > admin,...，而值作为数组的对象将包含对象

const user_permission = [ { _id: 1, description: 'chairman list', main_module: 'admin', sub_module: 'admin' }, { _id: 2, description: 'create chairman get method', main_module: 'admin', sub_module: 'admin' }, { _id: 3, description: 'create chairman post method', main_module: 'admin', sub_module: 'admin' }, { _id: 4, description: 'chairman list post', main_module: 'chairman', sub_module: 'chairman' }, { _id: 5, description: 'vendor list', main_module: 'vendor', sub_module: 'vendor' }, { _id: 6, description: 'vendor list post', main_module: 'vendor', sub_module: 'vendor' } ]
    
const res = user_permission.reduce((ac,a) => {
  let key = `${a.main_module} > ${a.sub_module}`
  if(!ac[key]) ac[key] = [];
  ac[key].push({[a._id]:a.description})
  return ac;


},{})

console.log(res)

Answer 2

您可以使用reduce来转换数据：

let user_permission =  [ 
{ _id: 1, description: 'chairman list',  main_module: 'admin',  sub_module: 'admin' },
{ _id: 2, description: 'create chairman get method', main_module: 'admin', sub_module: 'admin' },
{ _id: 3, description: 'create chairman post method', main_module: 'admin', sub_module: 'admin' },
{ _id: 4, description: 'chairman list post', main_module: 'chairman', sub_module: 'chairman' },
{ _id: 5, description: 'vendor list', main_module: 'vendor', sub_module: 'vendor' },
{ _id: 6, description: 'vendor list post', main_module: 'vendor', sub_module: 'vendor' } ]


let result = user_permission.reduce((prev, current) => {
    let key = `${current.main_module} > ${current.sub_module}`;
    let group = prev.find(x => x[key]);
    if(!group){
        group = { [key]: [] };
        prev.push(group);
    }    
    group[key].push({ [current._id]: current.description });
    return prev;
}, [])

console.log(result);

想要在Node.js中创建数组的数组（javascript）

2 个答案: