I've this nested array of object array:
const items = [
{
id: 1,
name: 'banana',
selected: true,
},
{
id: 2,
subItems: [
{
id: '2a',
name: 'apple',
selected: true,
},
{
id: '2b',
name: 'orange',
selected: false,
},
],
},
{
id: 3,
name: 'watermalon',
selected: true,
},
{
id: 4,
name: 'pear',
selected: false,
},
]
How can I get the ids base on selected property?
I manage to get the first level, I've tried
const selectedItemId = items.map(item => item.selected && item.id).filter(Boolean)
but how can I select the ids which is in the subItems? I expect the result to be [1, '2a', 3]
Flatten the array first. Be careful of using && item.id inside the mapper because that'll mean that falsey IDs (like 0, which is a reasonable starting number in some schemes) will be excluded.
const items=[{id:1,name:"banana",selected:!0},{id:2,subItems:[{id:"2a",name:"apple",selected:!0},{id:"2b",name:"orange",selected:!1}]},{id:3,name:"watermalon",selected:!0},{id:4,name:"pear",selected:!1}];
const output = items
.flatMap(item => [item].concat(item.subItems ?? []))
.filter(item => item.selected)
.map(item => item.id);
console.log(output);You can recursively traverse all the items and select the items that have selected set to true.
const items = [
{ id: 1, name: "banana", selected: true },
{
id: 2,
subItems: [
{ id: "2a", name: "apple", selected: true },
{ id: "2b", name: "orange", selected: false },
],
},
{ id: 3, name: "watermalon", selected: true },
{ id: 4, name: "pear", selected: false },
];
function getSelectedItems(items, selectedItems = []) {
for (let item of items) {
if (item.subItems) {
getSelectedItems(item.subItems, selectedItems);
} else if (item.selected) {
selectedItems.push(item.id);
}
}
return selectedItems;
}
console.log(getSelectedItems(items)); let newArray = [];
items.forEach(i=>{
if(i.selected){
newArray.push(i.id)
}
if(i.subItems){
i.subItems.forEach(j=>{
if(j.selected){
newArray.push(j.id)
}
})
}
});
so this is bit lengthy. with 2 map loops