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Push object into array without key in javascript

I want to push my object without a key in my javascript array. Right now the issue is I psuh my object in the array, but I add extra key 0,1,2 ... I don't want that key. Is there any solution for that? Here I add the code that I implemented.
let newArr = [];
let myId = data['id'];
var key = myId;
var obj = {};
myobj[key] = {
data: "testdata"
};
newArr.push(myobj);
The above code generates output like below. I don't want that 0 key in my array
0: {
260: {
data: 'testdata'
},
}

It's hard to tell what you're wanting, but I expect you don't want to be using an array here at all? You just want a single object that contains all of your key-value pairs?
e.g. something like this:
const data = { id: 1234 };
let myId = data['id'];
var key = myId;
var myobj = {};
myobj[key] = {
data: "testdata"
};
console.log(myobj);
// You can then add more data
myobj[2345] = {
data: "more test data"
};
console.log(myobj);
// Example Property Access
console.log(myobj[2345])

Try this
newArr.push(...myobj);

Getting child data in a JavaScript object

I have been banging my head against this all night.
I have a service that is returning data that looks like this:
You will see there are Objects with a GUID, nested under a parent object. I need to loop through all the "GUID" objects and get the attributes (i.e., author, content, etc.).
The GUIDs are dynamic (I don't know what they are ahead of time). The attributes below it are known.
I am having trouble figuring out how to target it. I can't seem to successfully use a for or forEach loop on it.
I need to use native JavaScript (i.e. no jQuery for this one).

Here's a possible solution:
var keys = Object.keys(data);
var results =
keys.map(
function(key){
var datum = data[key];
// do whatever with the data.
return {
"author" : data["author"]
}
}
)
// now results is an array of {"author"} objects.

var x = {
'a-45-2455': {
'author': 'Some Name'
}
};
var keys = Object.keys(x);
keys.forEach(function(key,value){
var author = x[key]['author'];
console.log(author);
});
You can access the data in this way.
You can also create another array from the values and use that.

In order to loop through an object use for...in
Since you have not posted the code of object , here is a snippet with dummy object
var x = {
'a-45-2455': {
'author': 'Some Name'
}
}
for(var keys in x){
alert(x[keys].author)
}

If you are using angular try angular.forEach loop to iterate over all GUID's, else you can use for each in javascript. see below code snippet.
var user ={
'1': {
"name":'abc',
"age":26
},
'2': {
"name":'def',
"age":28
}
};
for(var key in user) {
console.log(user[key].name);
}

Here is another way to iterate through json Object
var obj = {a: 1, b: 2, c: {a: 1, b: 2}};
function walk(obj) {
for (var key in obj) {
if (obj.hasOwnProperty(key)) {
var val = obj[key];
console.log(val);
walk(val);
}
}
}
walk(obj);
var obj = {a: 1, b: 2, c: {a: 1, b: 2}};
function walk(obj) {
for (var key in obj) {
if (obj.hasOwnProperty(key)) {
var val = obj[key];
console.log(val);
walk(val);
}
}
}
walk(obj);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

I believe that you can iterate through all indexes using the advanced for loop. a.b is the same as a["b"] in javascript.

You can iterate thru the object properties like this:
for(let key in Response){
if(!Response.hasOwnProperty(key))
continue;
//key will be each GUID
let yourObject = Response[key] //Each object in the list of objects
}
You can read about for...in loops here
Hope that helps!

Stringify an JS Object in Asc order

I have an js object like
{
a: 1,
b: 2,
c: 3
}
I wanted to stringify the above object using JSON.stringify with the same order. That means, the stringify should return me the strings as below,
"{"a":"1", "b":"2", "c":"3"}"
But it is returning me like the below one if my js object has too many properties say more than 500,
"{"b":"2", "a":"1", "c":"3"}"
Is there any option to get my js object's json string as in sorted in asc.

If the order is important for you, don't use JSON.stringify because the order is not safe using it, you can create your JSON stringify using javascript, to deal with string values we have 2 different ways, first to do it using regexp an replace invalid characters or using JSON.stringify for our values, for instance if we have a string like 'abc\d"efg', we can simply get the proper result JSON.stringify('abc\d"efg'), because the whole idea of this function is to stringify in a right order:
function sort_stringify(obj){
var sortedKeys = Object.keys(obj).sort();
var arr = [];
for(var i=0;i<sortedKeys.length;i++){
var key = sortedKeys[i];
var value = obj[key];
key = JSON.stringify(key);
value = JSON.stringify(value);
arr.push(key + ':' + value);
}
return "{" + arr.join(",\n\r") + "}";
}
var jsonString = sort_stringify(yourObj);
If we wanted to do this not using JSON.stringify to parse the keys and values, the solution would be like:
function sort_stringify(obj){
var sortedKeys = Object.keys(obj).sort();
var arr = [];
for(var i=0;i<sortedKeys.length;i++){
var key = sortedKeys[i];
var value = obj[key];
key = key.replace(/"/g, '\\"');
if(typeof value != "object")
value = value.replace(/\\/g, "\\\\").replace(/"/g, '\\"');
arr.push('"' + key + '":"' + value + '"');
}
return "{" + arr.join(",\n\r") + "}";
}

The JavaScript objects are unordered by definition (you may refer to ECMAScript Language Specification under section 8.6, click here for details ).
The language specification doesn't even guarantee that, if you iterate over the properties of an object twice in succession, they'll come out in the same order the second time.
If you still required sorting, convert the object into Array apply any sorting algorithm on it and then do JSON.stringify() on sorted array.
Lets have an example below as:
var data = {
one: {
rank: 5
},
two: {
rank: 2
},
three: {
rank: 8
}
};
var arr = [];
Push into array and apply sort on it as :
var mappedHash = Object.keys( data ).sort(function( a, b ) {
return data[ a ].rank - data[ b ].rank;
}).map(function( sortedKey ) {
return data[ sortedKey ];
});
And then apply JSON.stringy :
var expectedJSON = JSON.stringify(mappedHash);
The output will be:
"[{"rank":2},{"rank":5},{"rank":8}]"

Getting the first index of an object

Consider:
var object = {
foo: {},
bar: {},
baz: {}
}
How would I do this:
var first = object[0];
console.log(first);
Obviously, that doesn’t work because the first index is named foo,
not 0.
console.log(object['foo']);
works, but I don’t know it’s named foo. It could be named anything. I just want the first.

Just for fun this works in JS 1.8.5
var obj = {a: 1, b: 2, c: 3};
Object.keys(obj)[0]; // "a"
This matches the same order that you would see doing
for (o in obj) { ... }

If you want something concise try:
for (first in obj) break;
alert(first);
wrapped as a function:
function first(obj) {
for (var a in obj) return a;
}

they're not really ordered, but you can do:
var first;
for (var i in obj) {
if (obj.hasOwnProperty(i) && typeof(i) !== 'function') {
first = obj[i];
break;
}
}
the .hasOwnProperty() is important to ignore prototyped objects.

This will not give you the first one as javascript objects are unordered, however this is fine in some cases.
myObject[Object.keys(myObject)[0]]

If the order of the objects is significant, you should revise your JSON schema to store the objects in an array:
[
{"name":"foo", ...},
{"name":"bar", ...},
{"name":"baz", ...}
]
or maybe:
[
["foo", {}],
["bar", {}],
["baz", {}]
]
As Ben Alpert points out, properties of Javascript objects are unordered, and your code is broken if you expect them to enumerate in the same order that they are specified in the object literal—there is no "first" property.

for first key of object you can use
console.log(Object.keys(object)[0]);//print key's name
for value
console.log(object[Object.keys(object)[0]]);//print key's value

There is no way to get the first element, seeing as "hashes" (objects) in JavaScript have unordered properties. Your best bet is to store the keys in an array:
var keys = ["foo", "bar", "baz"];
Then use that to get the proper value:
object[keys[0]]

ES6
const [first] = Object.keys(obj)

Using underscore you can use _.pairs to get the first object entry as a key value pair as follows:
_.pairs(obj)[0]
Then the key would be available with a further [0] subscript, the value with [1]

I had the same problem yesterday. I solved it like this:
var obj = {
foo:{},
bar:{},
baz:{}
},
first = null,
key = null;
for (var key in obj) {
first = obj[key];
if(typeof(first) !== 'function') {
break;
}
}
// first is the first enumerated property, and key it's corresponding key.
Not the most elegant solution, and I am pretty sure that it may yield different results in different browsers (i.e. the specs says that enumeration is not required to enumerate the properties in the same order as they were defined). However, I only had a single property in my object so that was a non-issue. I just needed the first key.

You could do something like this:
var object = {
foo:{a:'first'},
bar:{},
baz:{}
}
function getAttributeByIndex(obj, index){
var i = 0;
for (var attr in obj){
if (index === i){
return obj[attr];
}
i++;
}
return null;
}
var first = getAttributeByIndex(object, 0); // returns the value of the
// first (0 index) attribute
// of the object ( {a:'first'} )

To get the first key of your object
const myObject = {
'foo1': { name: 'myNam1' },
'foo2': { name: 'myNam2' }
}
const result = Object.keys(myObject)[0];
// result will return 'foo1'

Based on CMS answer. I don't get the value directly, instead I take the key at its index and use this to get the value:
Object.keyAt = function(obj, index) {
var i = 0;
for (var key in obj) {
if ((index || 0) === i++) return key;
}
};
var obj = {
foo: '1st',
bar: '2nd',
baz: '3rd'
};
var key = Object.keyAt(obj, 1);
var val = obj[key];
console.log(key); // => 'bar'
console.log(val); // => '2nd'

My solution:
Object.prototype.__index = function(index)
{
var i = -1;
for (var key in this)
{
if (this.hasOwnProperty(key) && typeof(this[key])!=='function')
++i;
if (i >= index)
return this[key];
}
return null;
}
aObj = {'jack':3, 'peter':4, '5':'col', 'kk':function(){alert('hell');}, 'till':'ding'};
alert(aObj.__index(4));

method Array.push() javascript

I need to add a new item to array or change the item by id, but When I call the method push, it just creates a new item with a key 0,1,2...
I wrote this array
var finalArray = [];
button.addEventListener('click', function(){
id=123;
writeArray(id, "Jason");
//When I click the button, array always create a new item instead of change the item by id (123).
});
function writeArray(id, name){
var array = {
[id]:{
name: name
}
};
finalArray.push(array);
}
In result, array always creates a new item which is showing below. But I need to change the item by id.
0:{
123: {
name: "Chinga"
}
}
1:{
123: {
name: "Chinga"
}
}
2:{
123: {
name: "Chinga"
}
}
.
.
.

You currently push an object in an array everytime you call your writeArray method, which is not the objective.
As you want to edit an object, using it as a map pretty much, you should access the key (id) you want directly and set the desired value.
finalArray[id] = name;

when I call the method push, it just creates a new item with a key
0,1,2...
push will always add a new item, you need to first check if the item already exists.
function writeArray(id, name){
var index = finalArray.findIndex( function(item, index){
return Object.keys( item )[0] == id;
});
//existing logic
var array = {
[id]:{
name: name
}
};
if ( index == -1 )
{
finalArray.push(array);
}
else
{
finalArray[index] = array;
}
}

What you want is not an array, but an object.
// Initialize object.
var finalObject = {}; /* Changed [] to {} */
function writeToObject(id, name){
finalObject[id] = name;
};
If you still want to use an array, just write finalArray[id] = name but if you got 123 as a number (read: index), that will automatically create empty spaces up to index 123.

I think there are two approaches you can use here:
Instead of an array you can just use an object which simplifies the code pretty much:
finalObject = {};
finalObject[id] = name;
// Structure
finalObject = {'123': 'Jason', '1234': 'John'}
However, if you have to use an actual array, the solution would be to iterate through the array and check if an object with the given ID already exists and if so then modify the name property of it other case just push a new object to the array.
// Structure
finalArray = [{id: '123', 'Jason'}, {id: '1234', 'John'}]
Both could be valid solutions depending on your use case.