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How to convert Json into associative array or key value array

I have following Json which i need to insert into a table.
I want to convert each student detail into a row.
Because if i loop through the rows as per the existing structure i am reading one column as a row.
var json {
"Students":[
{
"name":{
"value":"Allan"
},
"number":{
"value":"123"
}
},
{
"name":{
"value":"Frank"
},
"number":{
"value":"456"
}
}
]
}
Ideally i want to the above as
{ "name": "Allan", "number": 123};
{ "name": "Frank", "number": 456};
I am looping through the Json as below
var objectKeys = Object.keys(json);
for (var key in objectKeys)
{
var student = json.Students;
for (var i = 0; i < student .length; i++) {
for (var column in json.Students[i]) {
window.print(column);
window.print(json.Students[i][column].value);
}
}
}
NOTE: No JQuery, want to achieve the above through normal Javascript.

If you want to transform the data, you can use Array.map
var json = {"Students":[{"name":{"value":"Allan"},"number":{"value":"123"}},{"name":{"value":"Frank"},"number":{"value":"456"}}]};
let result = json.Students.map(o => ({
name: o.name.value,
number: o.number.value
}));
console.log(result);
If you want to access the data, you can use Array.forEach
var json = {"Students":[{"name":{"value":"Allan"},"number":{"value":"123"}},{"name":{"value":"Frank"},"number":{"value":"456"}}]};
json.Students.forEach(o => console.log({name: o.name.value, number: o.number.value}));

var json = {
"Students":[
{
"name":{
"value":"Allan"
},
"number":{
"value":"123"
}
},
{
"name":{
"value":"Frank"
},
"number":{
"value":"456"
}
}
]
}
var studentData = JSON.stringify(json.Students);
var convertedData = JSON.parse(studentData.replace(/\{\"value\"\:/g,"").replace(/\}\,\"number/g,',"number').replace(/\"\}\}/g,'"}'));
Try this :)

No map or reduce. Just classic Javascript.
var json = {
"Students": [{
"name": {
"value": "Allan"
},
"number": {
"value": "123"
}
},
{
"name": {
"value": "Frank"
},
"number": {
"value": "456"
}
}
]
};
for (var student of json["Students"]) {
console.log(student); //your logic goes here.
}

how to add an element inside a json array at the specific index in a repeating block?

I am trying to add element "delete:true" after each occurrence of "_rev " mentioned in the below sample request.
Original Request:
{
"docs": [
{
"_id": "123",
"_rev": "1-7836",
},
{
"_id": "456",
"_rev": "1-1192",
}
]
}
Expected Request:
{
"docs": [
{
"_id": "123",
"_rev": "1-7836",
"_deleted" :true
},
{
"_id": "456",
"_rev": "1-1192",
"_deleted" :true
}
]
}
When I tried the below code,the ""_deleted" :true" is getting inserted after the -rev element is closed. PFB for the same and suggest.
function main(params) {
for (var i = 0; i< params.docs.length; i++) {
for (var value in params.docs[i]) {
if(value == '_rev' && params.docs[i]._rev ){
var string1 = JSON.stringify(params.docs[i]);
var str = ',';
var string2 = '"';
var string3 =str+string2+ '_deleted'+ string2+ ':' + "true" ;
var res = string1 + string3 ;
}
}
}
}
######################
[
"2018-01-23T09:44:23.568738362Z stdout:
{\"_id\":\"123\",
\"_rev\":\"1-7836\"},
\"_deleted\":true"]

Use map and Object.assign instead of generating a string
var output = params.docs.map( s => Object.assign( {}, {"_deleted" :true}, s ) );
You can then convert this to string using JSON.stringify( output );
Demo
var params = {
"docs": [{
"_id": "123",
"_rev": "1-7836",
},
{
"_id": "456",
"_rev": "1-1192",
}
]
};
var output = params.docs.map(s => Object.assign({}, {
"_deleted": true
}, s));
console.log(output);

var data = {
"docs": [
{
"_id": "123",
"_rev": "1-7836",
},
{
"_id": "456",
"_rev": "1-1192",
}
]
}
var newData = data['docs'].map(item => {
item._delete = true
return item
})
console.log(newData);

Why don't you simply put ._deleted attribute to doc, like this ?
function main(params) {
for (var i = 0; i< params.docs.length; i++) {
params.docs[i]._deleted = true;
var res = JSON.stringify(params.docs[i]);
}
}
}
Or like this :
function main(params) {
for (var i = 0; i< params.docs.length; i++) {
params.docs[i]["_deleted"] = true;
var res = JSON.stringify(params.docs[i]);
}
}
}

You can reference the not existing attribute directly and assign an value:
#!/usr/bin/js
var myJSON = { "docs": [ { "_id":"123", "_rev":"1-200" } ] }
console.log(myJSON);
myJSON.docs[0]["_deleted"]=true;
console.log(myJSON);
Output of example:
# js append.js
{ docs: [ { _id: '123', _rev: '1-200' } ] }
{ docs: [ { _id: '123', _rev: '1-200', _deleted: true } ] }
Read the more extensive example here: Add new attribute (element) to JSON object using JavaScript
So this might be a duplicate ...

Is there possible to loop inside JavaScript object literal

So this is my question (maybe stupid), is there any possible to do this:
var data {
"label" : value,
"sets" : [
for (var i=0; i < item.length; i++)
{
somedata: "data"
}
]
}
to reach result:
var data {
"label" : value,
"sets" : [
{
somedata: "data1"
},
{
somedata: "data2"
}
]
}
Much thx for help.

As jimm101 has pointed out, you are not working with JSON, that's just JavaScript (the var in there proves it) . If you want to calculate a value inside a literal JavaScript object, you can use an immediately invoked function
var data = {
"label" : value,
"sets" : (function(){
var arr = [];
for (var i=0; i < item.length; i++) {
arr.push( {somedata: "data" + i} ) ;
}
return arr;
})()
};
As dystroy has pointed out You can also use Array.map to return a transformed array, without needing an immediately invoked function, which looks a little nicer

You may use functional programming :
var data = {
"label" : "value",
"sets" : item.map(function(_,i){ return {somedata: "data"+(i+1)} })
}

Use the following:
var data = {
label: value,
get sets(){
var array = [];
/* write your logic to fill the array here. */
return array;
}
}
Reference here

As others have commented, JSON is data, not code. It looks like you're making javascript code though, since JSON also wouldn't include the var data part.
JSON => JavaScript Object Notation, a wide-spread way of representing data.
javascsript object => A structure within the javascript programming language that uses JavaScript Object Notation.
You can do something like this.
var data = {
"label" : 'my_label',
};
item = ['one','two','another'];
data.sets = [];
for (var i=0; i < item.length; i++)
{
data.sets.push({'somedata': item[i]});
}

You can use array comprehension (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Array_comprehensions), but it's not supported yet by all browsers (ECMAScript 6).
var value = "test";
var item = ["data1", "data2", "data3"];
var data = {
"label" : value,
"sets" : [for (x of item) {somedata: x}]
};
/*
Result :
data = {
"label":"test",
"sets":[
{"somedata":"data1"},
{"somedata":"data2"},
{"somedata":"data3"}
]
}
*/

You can have nested data in JSON like for example
var myObject = {
"first": "John",
"last": "Doe",
"age": 39,
"sex": "M",
"salary": 70000,
"registered": true,
"interests": [ "Reading", "Mountain Biking", "Hacking" ],
"favorites": {
"color": "Blue",
"sport": "Soccer",
"food": "Spaghetti"
},
"skills": [
{
"category": "JavaScript",
"tests": [
{ "name": "One", "score": 90 },
{ "name": "Two", "score": 96 }
]
},
{
"category": "CouchDB",
"tests": [
{ "name": "One", "score": 79 },
{ "name": "Two", "score": 84 }
]
},
{
"category": "Node.js",
"tests": [
{ "name": "One", "score": 97 },
{ "name": "Two", "score": 93 }
]
}
]
};
You can access such an array and its contents using a loop in your program
Source: http://www.json.com/

complex grouping and merging array as properties

I wish to put an array into other's array as proproties by matching their common properties. I want jobDetails's uId to match with job's uId. Possible?
var job = [{
"uId": 1
}, {
"uId": 2
}]
var jobDetails = [{
"uId": 1,
"salary": 5000
}, {
"uId": 2,
"salary": 5000
}]
is it possible to produce something like
var job = [{
"uId": 1,
"salary": [{
"uId": 1,
"salary": 5000
}]
}, {
"uId": 2,
"salary": [{
"uId": 2,
"salary": 5000
}]
}];

You may try something like this: http://jqversion.com/#!/XWFtbQb
for (var i = 0; i < job.length; i++) {
for (var j = 0; j < jobDetails.length; j++) {
if (job[i].uId == jobDetails[j].uId) {
job[i].salary = jobDetails[j];
}
}
}
console.log(job);

This is not a pure javascript solution, but I like to use underscore.js for this kind of typical actions on collections:
http://jsfiddle.net/FPwq7/
var finalCollection = [];
_.each(job, function(model){
var obj = _.findWhere(jobDetails, {uId: model.uId});
_.extend(model, {'salaray': obj});
finalCollection.push(model);
});
console.log(finalCollection);
I found that this Javascript utility belt takes care of some heavy lifting, and it makes the code a bit more pleasant to read than reading dry loops.

Yes possible , you need to play with both json objects
var array = [];
var object = {}
$.each( job, function ( k , kal ) {
$.each( jobDetails , function ( i , val) {
object.uId = i;
object.salary = val;
});
array.push(object);
});
console.log(JSON.stringify(array));

Create an object with custom structure in javascript

I need to create an array object with this exact structure:
{"item1": {
0 : {
color:"description1",
width:"description2",
height:"description3"
}
1 : {
color:"description1",
width:"description2",
height:"description3"
}
//and so on
},
"item2": {
0 : {
color:"description1",
width:"description2",
height:"description3"
}
//and so on
}
//and so on
}
Estatically works fine. Now, I want to make it dinamically. So, the main question is... How can I loop the data while constructing the object at the same time?
This is an example of the incoming object I work from:
[
{
"uid": 1,
"legendname": "item1",
"rows": [
{
"uid": 0,
"color": "482400",
"width": "482400",
"height": "25"
},
{
"uid": 1,
"color": "587898",
"width": "789658",
"height": "30"
}
]
}
{
"uid": 2,
"legendname": "item2",
"rows": [
{
"uid": 0,
"color": "482400",
"width": "482400",
"height": "25"
}
]
}
]

How can I loop the data while constructing the object at the same time?
Is not clear. But if you want to create a new structure based on the incoming one, you can use this:
// ar = your incoming object
// b_obj = your result
var b_obj = {}
for (var i = 0; i < ar.length; i++)
{
item = ar[i];
b_item = {};
for (var i_row = 0; i_row < item.rows.length; i_row++)
{
var row = {};
row.color = item.rows[i_row].color;
row.width = item.rows[i_row].width;
row.height = item.rows[i_row].height;
b_item[i_row] = row;
}
b_obj[item.legendname] = b_item;
}