I have the following array for example -
[
{
name: "abc",
value: "1"
},
{
name: "xyz",
value: "2"
},
{
name: "abc",
value: "3"
},
{
name: "abc",
value: "4"
},
{
name: "xyz",
value: "5"
},
]
Now, I want to reduce this array into a single object by grouping value with the same name together into an array. Something like this -
{
abc: [1, 3, 4],
xyz: [2, 5]
}
How do I do this using reduce in JavaScript?
I'm not sure if this the right approach but I have tried something like this and it doesn't give me the desired output.
const data = arr.reduce((acc, item) => {
return {
...acc,
[item.name]: [item.value, acc[item.value]]
};
});
You were on the right track with your answer, but you need to check if acc already has a key of item.name:
const data = [{
name: "abc",
value: "1"
},
{
name: "xyz",
value: "2"
},
{
name: "abc",
value: "3"
},
{
name: "abc",
value: "4"
},
{
name: "xyz",
value: "5"
},
]
const result = data.reduce((acc, { name, value }) => ({
...acc,
[name] : [...(acc[name] || []), value]
}), {})
console.log(result)Note you can use object destructuring to simplify the accumulation code.
const data=[
{
name: "abc",
value: "1"
},
{
name: "xyz",
value: "2"
},
{
name: "abc",
value: "3"
},
{
name: "abc",
value: "4"
},
{
name: "xyz",
value: "5"
},
];
const res=data.reduce((a,c)=>{
(a[c.name]??=[]).push(c.value);
return a;
},{});
console.log(res);const data = [{
name: "abc",
value: "1"
},
{
name: "xyz",
value: "2"
},
{
name: "abc",
value: "3"
},
{
name: "abc",
value: "4"
},
{
name: "xyz",
value: "5"
},
];
let finalObject = {};
data.forEach((item) => {
if (!finalObject.hasOwnProperty(item.name)) {
finalObject[item.name] = [item.value];
} else {
finalObject[item.name].push(item.value);
}
});
console.log(finalObject);Just parse values if you need in string to number and it will give you answer
{
abc: [1, 3, 4],
xyz: [2, 5]
}