I need to go through the array and find out if my array has children elements. Example any time i got array like a:
[
id: 1,
title: 'Parent',
children : [
{
id: 13,
title: 'Child'
}
]
any time i got array:
[
id: 1,
title: 'Parent',
children : [
{
id: 13,
title: 'Child'
},
{
id: 14,
title: 'Child two'
}
]
To explain better. The elements have their parent, child elements. What is my task? I need to find all the elements I get and put them in a array separately. So I need to extract these child elements from the array and put them in one array where all the elements are.
After looping of above array i need to get new array like:
FROM:
[
id: 1,
title: 'Parent',
children : [
{
id: 13,
title: 'Child'
},
{
id: 14,
title: 'Child two'
}
]
TO
[
{
id: 1,
title: 'Parent',
},
{
id: 13,
title: 'Child'
},
{
id: 14,
title: 'Child two'
}
]
Here is another recursive way of doing it:
The outer function collect(arr) provides a scope for the inner recursively called function getItems(). Whenever a child item is found the properties id and title are assembled into a new object and pushed into the results array res that was defined in collect().
const data=[{id:1,
title:'Parent',
children:[{id:13,
title:'Child'},
{id:14,
title:'Child two',
children: [{id:15,
title:'Grandchild'}]
}]},
{id:16,
title:'Uncle'}
];
function collect(arr){
const ret=[];
function getItems(ob){
ret.push({id:ob.id,title:ob.title});
if (ob.children) ob.children.forEach(getItems);
}
arr.forEach(getItems)
return ret
}
console.log(collect(data))Another one solution:
const data = [{"id":1,"title":"Parent","children":[{"id":13,"title":"Child"},{"id":14,"title":"Child two"}]}];
const flatObj = (arr) => arr.reduce((acc, { id, title, children }) => ([
...acc,
...(children) ? [{ id, title }, ...flatObj(children)] : [{ id, title }]
]), []);
console.log(flatObj(data));.as-console-wrapper{min-height: 100%!important; top: 0}Given an array of objects where an object will always have id, title and may or may not have the prop children, the stated/assumed objective is to transform this array into an array which only has id and title (including the children's id, title).
Sample Code
const getIdTitles = arr => (
arr.reduce(
(f, i) => (
{
...f,
[i.id] : i.title,
...(
'children' in i
? getIdTitles(i.children)
: {}
)
}
),
{}
)
);
Approach
reduce... spread-operator to first spread contents of the aggregator fid and titlechildren then recurseCode Snippet
const someArray = [{
id: 1,
title: 'Parent',
children : [
{
id: 13,
title: 'Child'
},
{
id: 14,
title: 'Child two'
}
]
}];
const getIdTitles = arr => (
arr.reduce(
(f, i) => (
{
...f,
[i.id] : i.title,
...(
'children' in i
? getIdTitles(i.children)
: {}
)
}
),
{}
)
);
console.log(getIdTitles(someArray))