i´m struggling with a Array in a Object stored in a Array with Objects from which I want return all Indicies.
Function to generate Object looks like this:
const addArray = function(a, b) {
const object = {
name: a,
rooms: b
};
testArray.push(object);
};
What I want to achieve is to cycle through the "testArray" and return every Index from the Object where the Array Rooms contains "Office" for example.
I´ve already tried to use a function like this but I don´t seem to be able to get the right Syntax for the Array in the Object:
function getAllIndexes(arr, val) {
var indexes = [], i = -1;
while ((i = arr.rooms.indexOf(val, i+1)) != -1){
indexes.push(i);
}
return indexes;
};
Thanks in advance!
Edit: Additional Informations to Data:
A Object with data filled would look like this:
const device = {
name: "TV",
rooms: ["Living Room", "Bedroom"]
};
After generating Objects like this I push them to an array witch only contains this objects (see function addArray
)
You can use Array.flatMap()
to map each value of the array at matches val
to it's index, and the rest to empty array, which will be removed by the flatMap:
const getAllIndexes =(arr, val) => arr.flatMap((v, i) => v === val? i: []) const arr = [1, 2, 3, 1, 2, 1, 1, 2] const result = getAllIndexes(arr, 1) console.log(result)
Using your array of objects, you'll need to compare a value, or check if an object meets some condition. It's better in this case to replace val
with a predicate function:
const getAllIndexes =(arr, pred) => arr.flatMap((v, i) => pred(v)? i: []) const arr = [{ rooms: [1, 2, 3] }, { rooms: [2, 1, 1] }, { rooms: [3, 2, 2] }, { rooms: [1, 2, 1] }] const result = getAllIndexes(arr, o => o.rooms.includes(1)) console.log(result)
Try using Array.prototype.map and Array.prototype.filter
function getAllIndexes(arr, val) {
return arr.map(i=> {
let room = i.rooms;
return room.indexOf(val);
}).filter(a=>{
a != -1;
});
};
You could destructure rooms
from the device and get the index, if the wanted value is found.
const
room = 'Office',
indices = array.flatMap(({ rooms }, i) => rooms.includes(room) ? i : []);
The above code features a former solution from me with hacking Array#flatMap
.
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