convert array of array of objects into single array of objects in lodash

Question

I have an array of arrays of objects as below which is generated by _.filter lodash function which returns objects for the matched values:

const matchedPositions = _.filter(allPositions, function(o) {
return o.company.toLowerCase() === value.toLowerCase();
});//matchedPositions have array of objects
let allCheckboxFiltered = [...allCheckboxFiltered, matchedPositions]; //allCheckboxFiltered  have below results

   [
    [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
    {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"}],
    [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
    {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
    {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"}]
    ];

I wanted as below intended result;

[
{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"}
];

I have tried reduce function to generate such intended result as below:

let result = temp1.reduce(function(res, obj) {
console.log(res, obj);
Object.keys(obj).forEach(function(k) {
res[k] = res[k] || [];
res[k] = res[k].concat(obj[k]);
});
return res;
}, []);

Above code is not generating the result, I wanted. I have tried other stuffs eg lodash functions as well but all in vain.

Thanks

Answer 1

You can use reduce

var output = temp1.reduce( (a,b) => (a = a.concat(b), a) ,[] ) ;

Or simply

var output = temp1.reduce( (a,b) => a.concat(b) ,[] ) ;

Answer 2

为什么不直接使用 lodash flatten https://lodash.com/docs/4.17.4#flatten

Answer 3

You can use reduce like below:

 var temp1 = [ [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}, {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}], [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}, {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}, {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}] ]; var result= temp1.reduce((o, m) => m.concat(o), []); console.log(result);

In case you want to play with more ES6 features:

 var temp1 = [ [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}, {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}], [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}, {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}, {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER"}] ]; var result= temp1.reduce((o, m) => [...m, ...o], []); console.log(result);

Answer 4

Use Lodash Library _.flattenDeep

let allCheckboxFiltered = [
    [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
    {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"}],
    [{serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
    {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"},
    {serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations  MANAGER"}]
    ];

allCheckboxFiltered = _.flattenDeep(allCheckboxFiltered);

Answer 5

You can use Array.concat in order to spread the inner array.

 var temp1 = [ [{ serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER" }, { serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER" } ], [{ serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER" }, { serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER" }, { serialNo: 9, sector: null, company: "AMERICAN LIFE INSURANCE COMPANY", location: null, position: "INSURANCE Operations MANAGER" } ] ]; const result = temp1.reduce((res, currentArr) => res.concat(currentArr), []) console.log(result);

Answer 6

只需使用下面的 Lodash 函数

_.flattenDeep(temp1);