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How to get keys from json object in javascript [closed]

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I have a json file:
[
{
"name": "Cocktail 1",
"ingredients": {
"rum": 12,
"coke": 48
}
}, {
"name": "Cocktail 2",
"ingredients": {
"gin": 24,
"tonic": 60
}
}]
Now I want to get a list of the keys of each "name" object. At the end there should be ths list
var mydata[0] = rum
var mydata[1] = coke
var mydata[2] = gin
var mydata[3] = tonic
and save it into an array.
What i have tried
var mydata = JSON.parse("jsonstring").ingredients;
hope this is understanable?

for each data in the array (map)
you want the ingredient part (.ingredients),
extract the keys (Object.keys)
and flatten the array (.flat())
array.map(a => a.ingredients).map(a => Object.keys(a)).flat();
You may prefer loop style. the only difference is flattening occurs with ... operator.
var results = [];
for (let a of array) {
results.push(...Object.keys(a.ingredients))
}

My proposition is :
'use strict'
const array = [
{
"name": "Cocktail 1",
"ingredients": {
"rum": 12,
"coke": 48
}
},
{
"name": "Cocktail 2",
"ingredients": {
"gin": 24,
"tonic": 60
}
}
]
const mydata = array.map((val) => {
return Object.keys(val.ingredients);
}).flat();
console.log(mydata)
// expected output: Array ["rum", "coke", "gin", "tonic"]
// Now you can get :
var mydata[0] = rum
var mydata[1] = coke
var mydata[2] = gin
var mydata[3] = tonic
Hope that help you? Thank

Convert plain array to Array of objects [closed]

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I have an array like this
let data = ['String1', 'String2', 'String3', 'String4']
I need to convert this array to an array of objects like so:
data = [
{value: 0, label: 'String1'},
{value: 1, label: 'String2'},
{value: 2, label: 'String3'},
{value: 3, label: 'String4'}
]
How to achieve this most elegantly?

Use map():
const arr = ['String1', 'String2', 'String3', 'String4'];
const res = arr.map((label, value) => ({ value, label }));
console.log(res);

How can i get my required data from array of objects using javascript? [closed]

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I have array of objects like this
var a = [
{'time' : 1539664755070,'T-1': 23 },
{'time' : 1539665095442,'H-1': 24 },
{'time' : 1539666489560,'T-1': 42 },
{'time' : 1539665095442,'H-1': 27 },
{'time': 1539671682230,'H-1': 40.45,'T-2': 33},
{'time': 1539671682230,'T-2': 30.45,'T-1': 65},
{'time': 1539671682230,'T-2': 42.45,'H-1': 11},
{'time': 1539671682230,'T-1': 50.45,'T-2': 85}
];
I want to have data like this
data : {
'T-1' : [23,42,50.45],
'T-2' : [33,30.45,85],
'H-1' : [24,27,40.45,11]
}
How can i get this data from given data?

Here is a solution, if something is not clear, please lemme know:
const result = {};
a.forEach(object => {
// Loop on each entry in the original array
Object.entries(object).forEach(([key,value]) => {
// Loop through each entry of one entry of the original array
// (ex 'T-1', 'T-2')
if(key !== 'time') {
// It's a key that I'm interested in, so do logic
if(!result[key]) {
// If the key (example 'T-1') haven't been encountered yet,
// initialize it's entry in the result with an empty array
result[key] = [];
}
result[key].push(value);
}
});
});

Best use case for using Map instead of Key,Value arrays. Simplifies lot of things.

You can use array#reduce with Object.values() to create a hash of your key and add the values corresponding to it. Then using Object.assign() and spread syntax you can create the final object.
let data = [ {'time' : 1539664755070,'T-1': 23 }, {'time' : 1539665095442,'H-1': 24 }, {'time' : 1539666489560,'T-1': 42 }, {'time' : 1539665095442,'H-1': 27 }, {'time': 1539671682230,'H-1': 40.45,'T-2': 33}, {'time': 1539671682230,'T-2': 30.45,'T-1': 65},{'time': 1539671682230,'T-2': 42.45,'H-1': 11}, {'time': 1539671682230,'T-1': 50.45,'T-2': 85} ],
result = Object.assign({}, ...Object.values(data.reduce((r, o) => {
let keys = Object.keys(o).filter(k => k !== 'time');
keys.forEach(key => {
r[key] = r[key] || {[key] : []};
r[key][key].push(o[key]);
});
return r;
},{})));
console.log(result);

const data = a.reduce((acc, row) => {
// Loop over keys of each row.
Object.keys(row)
// Filter out the "time" keys.
.filter((key) => key !== 'time')
// Collect the values by key, storing them in the accumulator.
.forEach((key) => {
if (typeof acc[key] === 'undefined') {
acc[key] = []
}
acc[key].push(row[key])
})
return acc
}, {})

JSON Object to Arrays [closed]

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Below JSON Object needs to be iterated and need result as below.
[
{"Aazam":1, "Jagannath":2, "Bharath Kumar M":4 },
{"Bharath Kumar M":1, "Syad":1 },
{"Bharath Kumar M":2 }
]
output needed (can be in map):
Aazam: 1
Jagannath: 2
Bharath Kumar M: 4, 1, 2
Syad: 1
I tried with ES 6 syntax, I am able to get key and values but I am not successful in forming the array as needed.
Solution should be generic.

You can have a object as a output with the unique keys and values for each key as an array that holds the values of all similar keys.
var arr = [{
"Aazam": 1,
"Jagannath": 2,
"Bharath Kumar M": 4
},
{
"Bharath Kumar M": 1,
"Syad": 1
},
{
"Bharath Kumar M": 2
}
];
var res = arr.reduce((acc, item) => {
var keys = Object.keys(item);
keys.forEach((key) => {
if (!acc[key]) {
acc[key] = [];
}
acc[key].push(item[key]);
});
return acc;
}, {});
console.log(res);

Sorting array of object based on range of Numbers of String [closed]

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I have an array of object like
let myObj =[{
"60+": 0.1413972485314015,
"18-29": 0.0832178903621611,
"40-49": 0.1033361204013377,
"30-39": 0.0835906328864075,
"Under 18": 0.1326368677036551,
"50-59": 0.1224973366151133
}]
I want to sort the above array of object like
let myObj =[{
"Under 18": 0.1326368677036551,
"18-29": 0.0832178903621611,
"30-39": 0.0835906328864075,
"40-49": 0.1033361204013377,
"50-59": 0.1224973366151133
"60+": 0.1413972485314015,
}]
How can i achieve this kind of sorting using javascript ?

You could take an offset for Under and + quantifier and take the value, depending on the sorting position. Then return the delta of values or the delta of the offset.
Later, you could build a new object with sorted keys.
var object = { "60+": 0.1413972485314015, "18-29": 0.0832178903621611, "40-49": 0.1033361204013377, "30-39": 0.0835906328864075, "Under 18": 0.1326368677036551, "50-59": 0.1224973366151133 },
keys = Object
.keys(object)
.sort((a, b) => {
function getV(s, side) {
var offset = { 'Under': -1, null: 0, '+': 1 }[s.match(/Under|\+/)],
value = s.match(/\d+/g)[offset && side];
return { value, offset };
}
var aa = getV(a, 1),
bb = getV(b, 0);
return aa.value - bb.value || aa.offset - bb.offset;
}),
newObject = Object.assign(...keys.map(k => ({ [k]: object[k] })));
console.log(newObject);
.as-console-wrapper { max-height: 100% !important; top: 0; }

You can use first character to sort and consider if first character is number it is small,
let myObj = [{
"60+": 0.1413972485314015,
"18-29": 0.0832178903621611,
"40-49": 0.1033361204013377,
"30-39": 0.0835906328864075,
"Under 18": 0.1326368677036551,
"50-59": 0.1224973366151133
}];
const ordered = {};
Object.keys(myObj[0]).sort(
function(a, b) {
if (isNaN(Number(a.charAt(0))))
return -1;
if (isNaN(Number(b.charAt(0))))
return 1;
return a.charAt(0) - b.charAt(0);
}
).forEach(function(key) {
ordered[key] = myObj[0][key];
});
console.log(ordered);

You can not do it directly. You have to change your structure. Something like this. I think the modified structure makes the same sense.
let myObj = [{
"60": 0.1413972485314015,
"29": 0.0832178903621611,
"49": 0.1033361204013377,
"39": 0.0835906328864075,
"18": 0.1326368677036551,
"59": 0.1224973366151133
}]
let result = Object.keys(myObj[0]).sort((a, b) => a - b).map(val => ({
[val]: myObj[0][val]
}));
console.log(result);