How to assign incremental index to nested array of object below? each members will have a property 1,2,3,4
groupMembersByTitle = [{
members: [{
id: 'uuid'
}, {
id: 'uuid'
}]
}, {
members: [{
id: 'uuid'
}, {
id: 'uuid'
}]
}]
I'm stuck here
const r = groupMembersByTitle.map(o => ({
...o,
members: o.members.map((o2, index) => ({
...o2,
no: ++index
}))
}))
You'll need a more persistent outer variable.
const groupMembersByTitle = [{
members: [{
id: 'uuid'
}, {
id: 'uuid'
}]
}, {
members: [{
id: 'uuid'
}, {
id: 'uuid'
}]
}];
let no = 1;
const mapped = groupMembersByTitle.map(
obj => ({
members: obj.members.map(
member => ({ ...member, no: no++ })
)
})
);
console.log(mapped);
You can use the map parameter thisArg.
map(function(element, index, array) { /* … */ }, thisArg)
const groupMembersByTitle = [{
members: [{ id: 'uuid' }, { id: 'uuid' }]
}, {
members: [{ id: 'uuid' }, { id: 'uuid' }]
}];
const r = groupMembersByTitle.map(function(o1) {
return ({
members: o1.members.map(
o2 => ({
...o2,
no: ++this.acc
})
)
});
}, { acc: 0 });
console.log(r);
function recursiveFunction(data, index) {
if(Array.isArray(data)) {
return data.reduce((acc, el) => this.recursiveFunction(el, acc), index);
} else if(data.members) {
return this.recursiveFunction(data.members, index);
} else {
data.no = index;
return index + 1;
}
}
const groupMembersByTitle = [
{
members: [
{
id: 'uuid'
},
{
id: 'uuid'
}
]
},
{
members: [
{
id: 'uuid'
},
{
id: 'uuid'
}
]
}];
const res = recursiveFunction(groupMembersByTitle, 0);
console.log(groupMembersByTitle);
console.log(res);
You can do it using Array.prototype.map twice and use the indices of the arrays to calculate the no.
const
data = [
{ members: [{ id: "uuid" }, { id: "uuid" }] },
{ members: [{ id: "uuid" }, { id: "uuid" }] },
],
result = data.map(({ members }, i) =>
members.map((m, j) => ({
...m,
no: i * (i ? data[i - 1].members.length : 1) + j + 1,
}))
);
console.log(result);
Related
Hi all I have following data:
const section = {
fileds: [
{ id: "some Id-1", type: "user-1" },
{
child: [
{ id: "some Id-2", type: "user-2" },
{ fileds: [{ id: "kxf5", status: "pending" }] },
{ fileds: [{ id: "ed5t", status: "done" }] }
]
},
{
child: [
{ id: "some Id-3", type: "teacher" },
{ fileds: [{ id: "ccfr", status: null }] },
{ fileds: [{ id: "kdpt8", status: "inProgress" }] }
]
}
]
};
and following code:
const getLastIds = (arr) =>
arr.flatMap((obj) => {
const arrayArrs = Object.values(obj).filter((v) => Array.isArray(v));
const arrayVals = Object.entries(obj)
.filter(([k, v]) => typeof v === "string" && k === "id")
.map(([k, v]) => v);
return [...arrayVals, ...arrayArrs.flatMap((arr) => getLastIds(arr))];
});
console.log(getLastIds(section.fileds));
// output is (7) ["some Id-1", "some Id-2", "kxf5", "ed5t", "some Id-3", "ccfr", "kdpt8"]
My code doing following, it printing in new array all ids.
It's working but I don't need all ids.
I need to return only last id in array and I should use recursion.
The output should be
(4) [" "kxf5", "ed5t", "ccfr", "kdpt8"]
P.S. here is my code in codesandbox
Is there a way to solve this problem with recursion? Please help to fix this.
You can do it with reduce.
function getLastIds (value) {
return value.reduce((prev, cur) => {
if (cur.id) {
return [ ...prev, cur.id ];
} else {
let key = ('child' in cur) ? 'child' : 'fileds';
return [ ...prev, ...getLastIds (cur[key]) ]
}
}, []);
}
You could check if a certain key exists and take this property for mapping id if status exists.
const
getValues = data => {
const array = Object.values(data).find(Array.isArray);
return array
? array.flatMap(getValues)
: 'status' in data ? data.id : [];
},
section = { fileds: [{ id: "some Id-1", type: "user-1" }, { child: [{ id: "some Id-2", type: "user-2" }, { fileds: [{ id: "kxf5", status: "pending" }] }, { fileds: [{ id: "ed5t", status: "done" }] }] }, { child: [{ id: "some Id-3", type: "teacher" }, { fileds: [{ id: "ccfr", status: null }] }, { fileds: [{ id: "kdpt8", status: "inProgress" }] }] }] },
result = getValues(section);
console.log(result);
I have an array
const a = [
{ name: "read-web-courses" },
{ name: "example" },
{ name: "t_gql" },
{ name: "ddddd" },
];
I am trying it to reduce it to the below given output , However I am stuck
Output
{0:"read-web-courses",1:"example",2:"t_gql",3:"ddddd"}
You could map the wanted property and assign the pairs to the object.
const
array = [{ name: "read-web-courses" }, { name: "example" }, { name: "t_gql" }, { name: "ddddd" }],
result = Object.assign({}, array.map(({ name }) => name));
console.log(result);
You can use Array.reduce like below.
const a = [
{ name: "read-web-courses" },
{ name: "example" },
{ name: "t_gql" },
{ name: "ddddd" },
];
const convert = arr => (
arr.reduce((total, value, index) => {
total[index] = value.name;
return total;
}, {})
)
console.log(convert(a));
This is accomplished using Array#reduce, where you can use the index from the reduce callback as the key of the new object:
const a = [ { name: "read-web-courses" }, { name: "example" }, { name: "t_gql" }, { name: "ddddd" }];
const res = a.reduce((r, o, i) => {
r[i] = o.name;
return r;
}, {});
console.log(res);
Also one more approach using Object#fromEntries and Array#map, where each object is converted to an array of key, value pairs:
const a = [ { name: "read-web-courses" }, { name: "example" }, { name: "t_gql" }, { name: "ddddd" }];
const res = Object.fromEntries(a.map((o, i) => [i, o.name]));
console.log(res)
I have an array of data which is a string of folders:
var data = [{ name: "/X" }, { name: "/X/Y" }, { name: "/X2" }, { name: "/X2/Z" }, { name: "/X/k" }]
For a component to display this items I need them sorted nested like these:
var data = [{ name: "/X", sub: [{ name: "/Y" }, { name: "/k" }]}, { name: "/X2" }, sub: [{ name: "/Z" }] }]
These items are just examples, the item count is 1000+ and the nested items can be unlimited too.
Any ideas how to do that?
You could do this with forEach and reduce methods and use one object to keep track of level based on the current part of the name property value.
const data = [{ name: "/X" }, { name: "/X/Y" }, { name: "/X2" }, { name: "/X2/Z" }, {name: '/X/K/1'}, {name: '/X/K/2'}]
const result = []
const level = {result}
data.forEach(({ name, ...rest }) => {
name.split('/').filter(Boolean).reduce((r, k) => {
if (!r[k]) {
r[k] = { result: [] }
r.result.push({
name: `/${k}`,
sub: r[k].result
})
}
return r[k]
}, level)
})
console.log(result)
Using reduce() and Map()
var data = [{ name: "/X" }, { name: "/X/Y" }, { name: "/X2" }, { name: "/X2/Z" }, { name: "/X/k" }]
var res = data.reduce((a, i) => {
let s = i.name.match(/\/\w+/g) || []
if (a.has(s[0])) {
let path = a.get(s[0])
i.name = s[1]
path.sub = path.sub || []
path.sub.push(i)
} else {
a.set(i.name, i)
}
return a
}, new Map())
console.log([...res.values()])
I'm attempting to convert an array that I get in this format:
data = [
{ name: 'Buttons/Large/Primary', id: '1:23' },
{ name: 'Buttons/Large/Secondary', id: '1:24' },
{ name: 'Buttons/Medium/Primary', id: '1:25' },
{ name: 'Buttons/Medium/Secondary', id: '1:26' },
{ name: 'Forms/Text', id: '2:1' },
{ name: 'Forms/Checkbox', id: '2:2' },
];
to an array in this format:
data = [
{
name: "Buttons",
id: '1:23',
components: [{
name: "Large",
id: '1:23',
components: [{
name: "Primary",
id: '1:23'
}, {
name: "Secondary",
id: '1:24'
}]
},{
name: "Medium",
id: '1:25',
components: [{
name: "Primary",
id: '1:25'
}, {
name: "Secondary",
id: '1:26'
}]
}]
}, {
name: "Forms",
id: '2:1',
components: [{
name: "Text",
id: '2:1'
},{
name: "Checkbox",
id: '2:2'
}]
}
];
My approach was to create arrays from each object in the original dataset by splitting the name property at '/', then nest them inside each other. This is what I have so far, which nests each item in the original array, but lacks grouping them together like my target format shows. Suggestions?
function nestItems(obj, path, value) {
let component = {};
let temp = component;
for (let i = 0; i < path.length; i++) {
let component = temp;
component.name = path[i];
component.id = value;
if (path.length - 1 === i) {
} else {
component.components = {};
temp = component.components;
}
}
obj.push(component)
}
let obj = [];
for (let i = 0; i < data.length; i++) {
let path = data[i].name.split('/');
nestItems(obj, path, data[i].id);
}
console.log(obj)
I agree with your approach for splitting with /.
Here's my approach for using reduce to create a map and generating the final array:
const data = [
{ name: 'Buttons/Large/Primary', id: '1:23' },
{ name: 'Buttons/Large/Secondary', id: '1:24' },
{ name: 'Buttons/Medium/Primary', id: '1:25' },
{ name: 'Buttons/Medium/Secondary', id: '1:26' },
{ name: 'Forms/Text', id: '2:1' },
{ name: 'Forms/Checkbox', id: '2:2' },
];
const map = data.reduce((acc, curr) => {
const { id } = curr;
const [parent, sub, subSub] = curr.name.split('/');
if (acc[parent]) {
if (acc[parent][sub]) {
acc[parent][sub][subSub] = { id };
} else {
acc[parent][sub] = { id };
if (subSub) {
acc[parent][sub][subSub] = { id };
}
}
} else {
acc[parent] = { id };
if (sub && subSub) {
acc[parent][sub] = {
id,
[subSub]: { id }
};
} else if (sub) {
acc[parent][sub] = { id };
};
}
return acc;
}, {});
const result = Object.keys(map).map(parentName => {
const { id: parentId, ...subs } = map[parentName];
const parentObj = { name: parentName, id: parentId };
parentObj.components = Object.keys(subs).map(subName => {
const { id: subId, ...subSubs } = subs[subName];
const subObj = { name: subName, id: subId };
if (Object.keys(subSubs).length) {
subObj.components = Object.keys(subSubs).map(subSubName => ({ name: subSubName, id: subSubs[subSubName].id }));
}
return subObj;
});
return parentObj;
});
console.log(result);
I have the following data structure:
const data = [
{
name: 'ABC',
salesData: [
{
timestamp: '2017-09-01',
value: 10
},
{
timestamp: '2017-09-02',
value: 2
}
]
},
{
name: 'DEF',
salesData: [
{
timestamp: '2017-09-01',
value: 8
},
{
timestamp: '2017-09-02',
value: 3
}
]
}
];
I would like to transform this to:
[
{
name: 'ABC',
'2017-09-01': 10,
'2017-09-02': 2
},
{
name: 'CDE',
'2017-09-01': 8,
'2017-09-02': 3
}
]
I'm trying to use Underscore's Chain and Map which I'm getting confused. So far I have the following, not sure how do I write the convertedSalesData to transform as per the need:
_.map(data, function(item) {
let name = item.name;
let salesData = item.salesData;
let convertedSalesData = ?
})
With ES6 you can use spread syntax ... to get this result.
const data = [{"name":"ABC","salesData":[{"timestamp":"2017-09-01","value":10},{"timestamp":"2017-09-02","value":2}]},{"name":"DEF","salesData":[{"timestamp":"2017-09-01","value":8},{"timestamp":"2017-09-02","value":3}]}]
var result = data.map(function({name, salesData}) {
return {name, ...Object.assign({}, ...salesData.map(({timestamp, value}) => ({[timestamp]: value})))}
})
console.log(result)
const data = [{
name: 'ABC',
salesData: [{
timestamp: '2017-09-01',
value: 10
},
{
timestamp: '2017-09-02',
value: 2
}
]
},
{
name: 'DEF',
salesData: [{
timestamp: '2017-09-01',
value: 8
},
{
timestamp: '2017-09-02',
value: 3
}
]
}
];
var res = data.map(function(a) {
var obj = {
name: a.name
};
a.salesData.forEach(function(x) {
obj[x.timestamp] = x.value;
})
return obj;
})
console.log(res);
Similar to #Nenad Vracar. I perfer to use 'reduce':
data.map(({ name, salesData }) => ({
name,
...salesData.reduce(
(record, { timestamp, value }) => {
record[timestamp] = value
return record
},
Object.create(null)
)
}))