creating a object from array of strings

Question

My input is like

var resources = ["user-john","user-doe", "students-Milan"];

I am trying to get an output as an object like below,

{
 user: ["john", "doe"],
 students: ["Milan"]
}

What am i doing wrong

var resources = ["user-john","user-doe", "students-Milan"];
let tempObj = {}
resources.forEach(o => {
 let tempArr = o.split("-");
 if(tempObj[tempArr[0]]){
 tempObj[tempArr[0]] = [...tempArr[1], tempArr[1]]
 }else{
 tempObj[tempArr[0]] = [tempArr[1]]
 }
})
console.log(tempObj)

Answer 1

You could deconstructure the splitted string and build an array as value.

var resources = ["user-john", "user-doe", "students-Milan"],
 result = resources.reduce(
 (r, s) =>
 ((key, value) => Object.assign(r, { [key]: [].concat(r[key] || [], value) }))
 (...s.split('-')),
 {}
 );
 
console.log(result);

Answer 2

You could use reduce method here with an object as a accumulator value.

var data = ["user-john", "user-doe", "students-Milan"];
var result = data.reduce((r, e) => {
 let [key, value] = e.split('-');
 r[key] = (r[key] || []).concat(value)
 return r;
}, {})
console.log(result)

Answer 3

A clean, modern solution:

var resources = ["user-john","user-doe", "students-Milan"];
const output = {}
resources.forEach(item => {
 const [key, value] = item.split('-') 
 output[key] = [...output[key] || [], value]
})
console.log(output)

Answer 4

Here in this part you actually need to :

resources.forEach(o => {
 let tempArr = o.split("-");
 if(tempObj[tempArr[0]]){
 tempObj[tempArr[0]] = [...tempObj[tempArr[0]], tempArr[1]];
 }else{
 tempObj[tempArr[0]] = [tempArr[1]]
 }
})

Answer 5

var resources = ["user-john","user-doe", "students-Milan"];
var tmp = {};
resources.forEach(function(e){
	var a = e.split("-");
	if(typeof tmp[a[0]] == "undefined"){
		tmp[a[0]] = [];
		tmp[a[0]].push(a[1]);
	}else{
		tmp[a[0]].push(a[1]);
	}
});
console.log(tmp);

Answer 6

You can use .push method instead [...tempArr[1], tempArr[1]]

var resources = ["user-john","user-doe", "students-Milan"];
let tempObj = {}
resources.forEach(o => {
 let tempArr = o.split("-");
 if(tempObj[tempArr[0]]){
 tempObj[tempArr[0]].push(tempArr[1])
 }else{
 tempObj[tempArr[0]] = [tempArr[1]]
 }
})
console.log(tempObj)

Or you can use the spread syntax on the last state of your array like [...tempObj[tempArr[0]], tempArr[1]] instead [...tempArr[1], tempArr[1]]