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How to convert array to single object? [closed]

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I have array object like this.
[
{
"name": "name1",
"type": "type1",
"car": "car1",
"speed": 1
},
{
"name": "name1",
"type": "type1",
"car": "car2",
"speed": 2
},
]
And i want to convert it single object for prevent data replay.
How can i do this?
{
"name": "name1"
"type": "type1",
"car": [
"car1",
"car2",
],
"speed": [
1,
2,
],
}
Could someone help me? Thanks.

If name and type can have same value and car and speed various,then below is a reference for you
Note: in order to get an expected answer(solution),you need to make you question more clear,the most important thing is the value of which properties various
const data = [
{
"name": "name1",
"type": "type1",
"car": "car1",
"speed": 1
},
{
"name": "name1",
"type": "type1",
"car": "car2",
"speed": 2
},
]
const result = data.reduce((a,v) =>{
let obj = a.find(i => i.name == v.name)
if(obj){
obj.car.push(v.car)
obj.speed.push(v.speed)
}else{
a.push({'name':v.name,'type':v.type,'car':[v.car],'speed':[v.speed]})
}
return a
},[])
console.log(result)

Logic to covert json stringify into multiple array [closed]

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var result = [
{
"Name": "abc",
"age": 12,
"City": "Mumbai",
"id":"U121"
},
{
"Name": "jkl",
"age": 22,
"City": "Mumbai",
"id":"U122"
},
{
"Name": "xyz",
"age": 32,
"City": "Mumbai",
"id":"U123"
},{
"Name": "mno",
"age": 42,
"City": "Mumbai",
"id":"U124"
}
]
I want to iterate this in javascript and create td, tr element in such a way that abc, jkl come in one row and xyz, mno come in second row. Can anyone help me with the logic?

You can try something like this
var input = [
{
"Name": "abc",
"age": 12,
"City": "Mumbai",
"id":"U121"
},
{
"Name": "jkl",
"age": 22,
"City": "Mumbai",
"id":"U122"
},
{
"Name": "xyz",
"age": 32,
"City": "Mumbai",
"id":"U123"
},{
"Name": "mno",
"age": 42,
"City": "Mumbai",
"id":"U124"
}
];
function test(){
let i=0;
let outhtml="";
input.forEach(ele => {
i=i%2;
let addRow=(i==0);
//After 2 elements add row
if (addRow){
outhtml += "</tr><tr>"
}
//add td
outhtml += "<td>"+ele.Name+"</td>"
i++;
})
//Remove </tr> from start
outhtml = outhtml.substring(5, outhtml.lenght);
document.getElementById("mytable").innerHTML = outhtml;
}
test();
<table id="mytable">
</table>

How to write only pure JS(no jquery or anything) code for reading JSON data from external '.js' file? [closed]

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Note : Using only pure JS, no addons, please provide a sample example
Sample data js file content -
var TABLE_DATA = [
{
"id": "5",
"name": "cony #5",
"thumbnailUrl": "image/5.gif",
"price": 170
},
{
"id": "1",
"name": "cony #1",
"thumbnailUrl": "image/1.gif",
"price": 170
},
{
"id": "2",
"name": "cony #2",
"thumbnailUrl": "image/2.gif",
"price": 270
},
{
"id": "8",
"name": "cony #8",
"thumbnailUrl": "image/8.gif",
"price": 70
},
{
"id": "10",
"name": "<img onerror='window.document.body.innerHTML = \"<h1>XSS</h1>\";' src=''> ",
"thumbnailUrl": "image/10.gif",
"price": 170
},
{
"id": "4",
"name": "cony #4",
"thumbnailUrl": "image/4.gif",
"price": 150
},
{
"id": "3",
"name": "cony #3",
"thumbnailUrl": "image/3.gif",
"price": 130
},
{
"id": "6",
"name": "cony #6",
"thumbnailUrl": "image/6.gif",
"price": 160
},
{
"id": "9",
"name": "cony #9",
"thumbnailUrl": "image/9.gif",
"price": 170
},
{
"id": "7",
"name": "cony #7",
"thumbnailUrl": "image/7.gif",
"price": 170
}
]

js has inbuilt JSON.parse(YOUR_JSON_FILE) method for parsing json.
In your example it is a json array.
So you may use for loop to go through each individual jsons.
const length = TABLE_DATA.length;
for(var i =0 ;i< length;i++) {
var jsObject = JSON.stringify(TABLE_DATA[i]);
console.log(jsObject);
//To read id
console.log(jsObject.id)
//To read name
console.log(jsObject.name)
//and so on
}
REMEMBER : JSON.parse turns a string of JSON text into a JavaScript
object
JSON.stringify turns a JavaScript object into JSON text and stores
that JSON text in a string
To LOAD_IN data from file click here : Loading Local Json File
May it Help You!

To load your external file, it must be made available on some place that your script is able to access (e.g. a web server). If you place the data as pure JSON (without var TABLE_DATA), you can load this data using the XMLHttpRequest, something along the lines of the following:
const xhttp = new XMLHttpRequest()
xhttp.onreadystatechange = function() {
if (this.readyState ==4 && this.status==200) {
data = JSON.parse(this.responseText)
// do stuff with your data
}
}
xhttp.open(URL_TO_THE_JSON)
xhttp.send()

hierarchical json data from flat json [closed]

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I have parent-child JSON data and I want to get all children (nested children) from a selected parent in the specific year-wise data format as below
var data = [{ "Id": "1", "Name": "abc", "EnteredOn": "03/01/2019", "attr": "abc" },
{ "Id": "2", "Name": "abcd", "EnteredOn": "02/01/2018", "attr": "abc" },
{ "Id": "3", "Name": "abcde", "EnteredOn": "04/01/2019", "attr": "abc" },
{ "Id": "4", "Name": "abcdef", "EnteredOn": "01/01/2016", "attr": "abc" }];
output:
{
"year": "2019",
"children": [
{
"ID": "1",
"Name": "abc",
"Date": "03/01/2019"
}
]
}

First, i recommend adding year attribute
data.forEach(a=> a['year'] = a.EnteredOn.getFullYear()
and using Lodash _.groupBy function
data.groupBy("year")

JavaScript: How can I transform objects array A to objects array B in the efficiency way? [closed]

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I got object array A as this:
[
{
"Timestamp": "2015-10-01 00:00:00",
"Label": "Voltage",
"Value": "230.12"
},
{
"Timestamp": "2015-10-01 00:00:00",
"Label": "Frequency",
"Value": "50.12"
},
{
"Timestamp": "2015-10-01 00:00:00",
"Label": "Power",
"Value": "23"
},
{
"Timestamp": "2015-10-02 22:22:22",
"Label": "Voltage",
"Value": "231.12"
},
{
"Timestamp": "2015-10-02 22:22:22",
"Label": "Frequency",
"Value": "51.12"
},
{
"Timestamp": "2015-10-02 22:22:22",
"Label": "Power",
"Value": "23.4"
}
]
I want to transform to object array B as this:
[
{
"Timestamp": "2015-10-01 00:00:00",
"Voltage": "230.12",
"Frequency": "50.12",
"Power": "23"
},
{
"Timestamp": "2015-10-02 22:22:22",
"Voltage": "231.12",
"Frequency": "51.12",
"Power": "23.4"
}
]
I was looping to get the timestamp and re-loop again to get label and value to form new object array. It works but when the data become few hundred thousands object array then it's not efficiency and crash the browser. Would someone can think of a better way please. Thanks very much.

JSON is just a transport/storage format. It's generally not something you should attempt to manipulate directly. Best to manipulate the actual JavaScript objects/arrays.
If you can guarantee the original array sort order, try something like this:
var outputArray = [];
var currentObj = null;
originalArray.forEach(function (measurement) {
if (!currentObj || currentTimestamp !== measurement.Timestamp) {
currentTimestamp = measurement.Timestamp;
currentObj = {
Timestamp: measurement.Timestamp;
}
outputArray.push(currentObj);
}
currentObj[measurement.Label] = measurement.Value;
});
Then, you can just loop through and build the new array as you go.

As your desired output showed ignoring the time of the timestamp this will trim that part of the timestamp - if that was a mistake in the question I think you should be able to remove that part by yourself
var b = a.reduce((acc, cur) => {
var strippedTimestamp = cur.Timestamp.substring(1, 10) + " 00:00:00";
var obj = acc.find(e => e.Timestamp == strippedTimestamp);
if (!obj) {
obj = { Timestamp: strippedTimestamp };
acc.push(obj);
}
obj[cur.Label] = cur.Value;
return acc;
}, []);
will output
[
{
"Timestamp": "015-10-01 00:00:00",
"Voltage": "230.12",
"Frequency": "50.12",
"Power": "23"
},
{
"Timestamp": "015-10-02 00:00:00",
"Voltage": "230.12",
"Frequency": "50.12",
"Power": "23"
}
]