I have a JSON object that is similar to below:
vehicles:
{
trucks: [
"Ford",
"Toyota",
"Dodge",
],
suvs: [
"Honda",
"GMC",
],
cars: [
"Pontiac",
"Lotus",
"Aston-Martin",
"Porsche",
"Subaru"
]
}
I would like to loop through this and create my own object, however I cannot find out how to do it without using three different loops for each type of vehicle.
Here is my attempt below:
let vehicleObject = {
vehicles: []
}
// I'm getting the response back from a http request
Object.keys(body.vehicles).forEach(function (k) {
for (let i = 0; i < body.vehicles.k.length; i++) {
vehicleObject.vehicles.push({
vehicle_type: k,
manufacturer: body.vehicles.k[i]
});
}
});
However, this just leads me to "cannot read property length of undefined. I know I can accomplish this with a switch or three if's but I would like to learn a more efficient way, if possible. Thank you.
Loop should be like this:
Object.keys(body.vehicles).forEach(function (k) {
for (let i = 0; i < body.vehicles[k].length; i++) {
vehicleObject.vehicles.push({
vehicle_type: k,
manufacturer: body.vehicles[k][i]
});
console.log(vehicles[k].length)
}
});
When you iterate over each key you are getting name of the keys in k and then to get the array from body.vehicles object you need to do something like body.vehicles[k].
To declare global variable for the scope you should probably use var instead of let
var vehicleObject = {
vehicles: []
};
let is reachable only inside {...} block, like you used it in your for {...} loop.
Looks like you want an array of objects, like:
[{ vehicle_type: 'suvs', manufacturer: 'Honda' }, ... ]
Assuming, body contains the vehicles object:
const { vehicles } = body
const vehicleTypes = Object.keys(vehicles)
const getManufacturers = type => vehicles[type]
const createVehicle = (type, mf) => ({ vehicle_type: type, manufacturer: mf })
let flattenedVehicles = []
vehicleTypes.forEach(type => {
flattenedVehicles.push(
getManufacturers(type).map(mf => createVehicle(type, mf))
)
})
// flattenedVehicles now has desired array
Related
I want to merge values from an array into a static nested object. The array containing the values is something like this,
['name=ABC XYZ', 'hobbies=[M,N,O,P]', 'profession=S', 'age=27']
and the object in which the values has to be merged is,
const person = {
details_1: {
name: null,
hobbies: null,
profession: null
},
details_2: {
age: null
}
};
I want my output object to look like below,
const updated_person = {
details_1: {
name: 'ABC XYZ',
hobbies: [M,N,O,P],
profession: 'S'
},
details_2: {
age: 27
}
};
Thanks a lot for your help!
I made another solution with a different approach.
Here I used an interface weher I described the desired data structure.
In the second part the string array is tranformed into key and value pairs. Thereform are filtered the keys of interface and added into an empty object literal.
const data = ["name=ABC XYZ", "hobbies=[M,N,O,P]", "profession=S", "age=27"];
const dataInterface = {
details_1: { name: null, hobbies: null, profession: null },
details_2: { age: null },
};
function orederData(arr) {
const record = arr.map((item) => {
let [key, value] = item.split("=");
if (value[0] === "[" && value[value.length - 1] === "]") {
value = value.slice(1, value.length - 1).split(",");
}
return { key, value };
});
const dataBlock = {};
Object.keys(dataInterface).map((detail) => {
dataBlock[detail] = {};
Object.keys(dataInterface[detail]).forEach((dataKey) => {
dataBlock[detail][dataKey] = record.filter((record) => {
return record.key === dataKey;
})[0].value;
});
});
return dataBlock;
}
const orderedData = orederData(data);
console.log(orderedData);
You can simply achieve this by iterating the input array.
const arr = ['name=ABC XYZ', 'hobbies=[M,N,O,P]', 'profession=S', 'age=27'];
const person = {
details_1: {},
details_2: {}
};
arr.forEach(item => {
(item.split('=')[0] !== 'age') ? person.details_1[item.split('=')[0]] = item.split('=')[1] : person.details_2[item.split('=')[0]] = item.split('=')[1]
});
console.log(person);
There is no way to cleanly merge an unstructured array into a structured object such that the array values end up in the appropriately keyed person properties.
javascript does provide the assign() function that merges objects but for YOUR requirements your source data needs to be an object similarly structured and not an array.
so this:
['name=ABC XYZ', 'hobbies=[M,N,O,P]', 'profession=S', 'age=27']
would need to become this:
const source= [{details_1: {"name":"ABC XYZ", "hobbies":"[M,N,O,P]", "profession":"S"}, details_2: {"age":"27"}}]
such that a call to Object.assign():
const new_person = Object.assign(person, source[0]);
fills this
const person = {
details_1: {
name: null,
hobbies: null,
profession: null
},
details_2: {
age: null
}
};
properly, though you may need to clone or instantiate and empty person first.
or, if person is an Object you could have a fill() method that knows what to do with the array data.
I have a list of objects like this
var obj = [
{ name: "user", per: { pu: [{ end: "foo" }], ge: [{ end: "bar" }] } },
{ name: "user2", per: { pu: [{ end: "foo2" }], ge: [{ end: "bar2" }] } }
];
I want to add a new property cond which is a function to the objects in pu and ge, but when i do this, the function set to the only last object.
I loop through them then set them like so obj[0].per[itm][0].cond = func and that set to the last object only, but when i try to convert function toString() it set to all, JSON.stringfy() works as func same behavior.
Have I clone or set it in another way?
You may need to post fuller code as it's difficult to see where your error is. However, considering it from scratch, I think some nested loops to match the nested arrays will get you there.
for (let o of obj) {
for (let puObj of o.per.pu) {
puObj.cond = func;
}
for (let geObj of o.per.ge) {
geObj.cond = func;
}
}
use the below function...
const updateObject = (oldObject, updatedProperties) => {
return {
...oldObject,
...updatedProperties
}
};
then you can pass in your new function or anything you need to add like this:
obj[index].per = updateObject(obj[index].per, {cond : function() {}} ); //use a loop to add the function to all objects in array
//check your current obj
console.log(obj);
I am building an typescirpt dictionary like that:
const skills = x
.map(y => y.skills)
.flat(1)
.map(z => {
return { [z.id]: { skill: z } };
});
That is the array I am getting by the code above:
{ 7ff2c668-0e86-418a-a962-4958262ee337: {skill: {…}} }
{ c6846331-2e11-45d6-ab8d-306c956332fc: {skill: {…}} }
{ 0fc0cb61-f44d-4fd0-afd1-18506380b55e: {skill: {…}} }
{ 36dc0b74-84ee-4be2-a91c-0a91b4576a21: {skill: {…}} }
Now the issue is I can not access the dictionary by key:
const id = '7ff2c668-0e86-418a-a962-4958262ee337';
const one = myArr.find(x => x === id); // returns undefined
const two = myArr[id]; // returns undefined
Any ideas how to fix?
You can use Object.keys() to get the key of each of your objects. In your case the key of each of your objects is its id. Then use that to check whether it equals x (you search id).
See example below:
const myArr = [
{"7ff2c668-0e86-418a-a962-4958262ee337": {skill: 1}},
{"c6846331-2e11-45d6-ab8d-306c956332fc": {skill: 2}},
{"0fc0cb61-f44d-4fd0-afd1-18506380b55e": {skill: 3}},
{"36dc0b74-84ee-4be2-a91c-0a91b4576a21": {skill: 4}}],
id = "36dc0b74-84ee-4be2-a91c-0a91b4576a21",
one = myArr.findIndex(x => Object.keys(x)[0] === id); // the index of the object which has the search id as its key.
myArr[one] = {newKey: "newValue"}; // set the index found to have a new object
console.log(myArr);
You are now creating an array of objects. I suggest you create an object instead, with your ids as keys
Example:
const skills = x
.map(y => y.skills)
.flat(1)
.reduce((acc, z) => {
acc[z.id] = z;
return acc;
}, {});
Your myArr is going to look something like:
{
'7ff2c668-0e86-418a-a962-4958262ee337': {...}
'c6846331-2e11-45d6-ab8d-306c956332fc': {...},
'0fc0cb61-f44d-4fd0-afd1-18506380b55e': {...},
'36dc0b74-84ee-4be2-a91c-0a91b4576a21': {...}
}
You can then access it the way you intended:
const skill = myArr['7ff2c668-0e86-418a-a962-4958262ee337'];
make use of map that can help,
Map is a new data structure introduced in ES6. It allows you store key-value pairs similar to other programming languages e.g. Java, C#.
let map = new Map();
const skills = x
.map(y => y.skills)
.flat(1)
.map(z => {
map.set(z.Id, { skill: z })
return map;
});
//Get entries
amp.get("7ff2c668-0e86-418a-a962-4958262ee337"); //40
//Check entry is present or not
map.has("7ff2c668-0e86-418a-a962-4958262ee337"); //true
How to add attribute to the root of JSON object consists of array of objects?
If my JSON object something like that:
[
{
"Id":"f2ac41c5-b214-48f6-ad40-9fc35c1aaad9",
"Name":"W",
"NumberOfWorkHours":8,
"NumberOfShortDays":1,
"WorkTimeRegulationId":"f5833075-2847-4cc3-834d-6138dd0dcd99"
},
{
"Id":"5c267601-fcf2-4735-9e49-b4def3981648",
"Name":"S",
"NumberOfWorkHours":6,
"NumberOfShortDays":0,
"WorkTimeRegulationId":"8d14580e-278f-41d1-9239-8874be792580"
}
]
I do the following:
worktimeJSON.Id = $('.Js-WorkTime-id').val();
worktimeJSON.Name = $('.Js-WorkTime-name').val();
worktimeJSON.NumberOfAvailableRotations = $('.Js-WorkTime-rotations').val();
And make sure that the jQuery fetching data from the inputs but this doesn't work.
This will change property of all object in array if you want to change in particular then use index for this for exp->
worktimeJSON[0].Id = $('.Js-WorkTime-id').val();
worktimeJSON[0].Name = $('.Js-WorkTime-name').val();
worktimeJSON[0].NumberOfAvailableRotations = $('.Js-WorkTime-rotations').val();
var worktimeJSON = [
{
"Id":"f2ac41c5-b214-48f6-ad40-9fc35c1aaad9",
"Name":"W",
"NumberOfWorkHours":8,
"NumberOfShortDays":1,
"WorkTimeRegulationId":"f5833075-2847-4cc3-834d-6138dd0dcd99"
},
{
"Id":"5c267601-fcf2-4735-9e49-b4def3981648",
"Name":"S",
"NumberOfWorkHours":6,
"NumberOfShortDays":0,
"WorkTimeRegulationId":"8d14580e-278f-41d1-9239-8874be792580"
}
];
worktimeJSON = worktimeJSON.map(function(val){
val.Id = $('.Js-WorkTime-id').val();
val.Name = $('.Js-WorkTime-name').val();
val.NumberOfAvailableRotations = $('.Js-WorkTime-rotations').val();
return val;
});
Push can do the job.
let worktimeJSON = [
{
"Id":"f2ac41c5-b214-48f6-ad40-9fc35c1aaad9",
"Name":"W",
"NumberOfWorkHours":8,
"NumberOfShortDays":1,
"WorkTimeRegulationId":"f5833075-2847-4cc3-834d-6138dd0dcd99"
},
{
"Id":"5c267601-fcf2-4735-9e49-b4def3981648",
"Name":"S",
"NumberOfWorkHours":6,
"NumberOfShortDays":0,
"WorkTimeRegulationId":"8d14580e-278f-41d1-9239-8874be792580"
}
];
worktimeJSON.push
({
id: "someID",
name: "toto",
WorkTimeRegulationId: 42
});
console.log(worktimeJSON);
I structure my object like this:
let WorkTimeRegulationViewModelJSON = {
Id: $('.Js-WorkTimeRegulation-id').val(),
Name: $('.Js-WorkTimeRegulation-name').val(),
NumberOfAvailableRotations: $('.Js-WorkTimeRegulation-rotations').val(),
AssignedWorkTimes: JSON.parse(worktimeJSON)
};
I am trying to convert an object to a leaner version using destructuring.
My object includes a nested array which also contains objects, from this array I would only like a few fields.
I can do the nested object destructuring fine, and the array destructuring fine but not together?
My current try looks like this:
var data = {
title: "title1",
bar: "asdf",
innerData: [
{
title: "inner-title1",
foo: "asdf"
},
{
title: "inner-title2",
foo: "asdf"
}
]
};
var { title, innerData: [ { title} ] } = data;
console.log(title);
for (var { title} of innerData) {
console.log(title);
}
But get a message saying innerData is not defined.
The outcome I would like might be:
{
title: "title1",
innerData: [
{
title: "inner-title1"
},
{
title: "inner-title2"
}
]
};
You can adjust the variable name to an identifier other than defined innerData ; use .map() or JSON.stringify(), JSON.parse() to filter title property from innerData objects
var {title, titles = data.innerData.map(o => ({title:o.title}))} = data;
to maintain innerData variable name you can use array destructuring of object
var [title, innerData] = [data.title, data.innerData.map(o => ({title:o.title}))];
using JSON.stringify(), JSON.parse()
var [title, innerData] = JSON.parse(JSON.stringify([data.title, data.innerData], ["title"]));
Edit
If requirement is to create an array containing all title properties within data you can use JSON.stringify() with replacer array set to ["title"], JSON.parse(), spread element
var data = {
title: "title1",
bar: "asdf",
innerData: [
{
title: "inner-title1",
foo: "asdf"
},
{
title: "inner-title2",
foo: "asdf"
}
]
};
var innerData = JSON.parse(JSON.stringify([data, ...data.innerData], ["title"]))
console.log(innerData);
Your destructuring doesn't do what you think.
var { title, innerData: [ { title} ] } = data;
is (essentially) equivalent to
var title = data.title;
var title = data.innerData[0].title;
Destructuring pulls out individual values, it will not map through the array for you. You'll need to do that manually if that is what you want.
As per #loganfsmyth suggested, I will do it in two steps.
var { title } = data;
for (var { title } of data.innerData) {
console.log( title );
}
Edit: my final solution to build a new json object from the old
const request = { innerData: [] };
({ title } = this.data);
for (const { title} of this.data.innerData) {
request.innerData.push({
title
});
}