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How to fetch values from json array object without using object key name javascript?

Json Array Object
Through Ajax I will get dynamic data which is not constant or similar data based on query data will change. But I want to display charts so I used chartjs where I need to pass array data. So I tried below code but whenever data changes that code will break.
I cannot paste complete JSON file so after parsing it looks like this
[{"brand":"DUNKIN' DONUTS KEURIG","volume":1.9,"value":571757},{"brand":"MC CAFE","volume":1.1,"value":265096}];

You can use Object.keys and specify the position number to get that value
var valueOne =[];
var valueTwo = [];
jsonData.forEach(function(e){
valueOne.push(e[Object.keys(e)[1]]);
valueTwo.push(e[Object.keys(e)[2]]);
})

It seems like what you're trying to do is conditionally populate an array based the data you are receiving. One solution might be for you to use a variable who's value is based on whether the value or price property exist on the object. For example, in your forEach loop:
const valueOne = [];
jsonData.forEach((e) => {
const val = typeof e.value !== undefined ? e.value : e.average;
valueOne.push(val);
})

In your jsonData.forEach loop you can test existence of element by using something like:
if (e['volume']===undefined) {
valueone.push(e.price);
} else {
valueone.push(e.volume);
}
And similar for valuetwo...

You could create an object with the keys of your first array element, and values corresponding to the arrays you are after:
var data = [{"brand":"DUNKIN' DONUTS KEURIG","volume":1.9,"value":571757},{"brand":"MC CAFE","volume":1.1,"value":265096}];
var splitArrays = Object.keys(data[0]).reduce((o, e) => {
o[e] = data.map(el => el[e]);
return o;
}, {});
// show the whole object
console.log(splitArrays);
// show the individual arrays
console.log("brand");
console.log(splitArrays.brand);
console.log("volume");
console.log(splitArrays.volume);
// etc

The key value of one object is changing on update of other similar type of object in javascript

I am using two different array object initialPermissionArr[item.id] and newPermissionArr[roleId] in two different functions
function(item){
vm.initialPermissionArr[item.id] = item.permissions.map(function (permission) {
permission.status = true;
return permission;
});
}
staticArr[item.id] = item.permissions.map(function (permission) {
permission.status = true;
return permission;
});
newpermissionArr[item.id] = vm.initialPermissionArr[item.id];
Below function updates the array, if same object is found it updates the status and if new object is found it pushes to newPermissionArr
function onChanageOfPermission(roleId,item) {
var flag = false ;
for (var key in newpermissionArr[roleId]){
if(newPermissionArr[roleId][key].id == item.id){
flag = true;
newPermissionArr[roleId][key].status = item.status;
break;
}
}
if (!flag) {
newPermissionArr[roleId].push(item);
}
}
So when newPermissionArr[roleId][key].status = item.status; is updated it also update the status in the initialPermissionArr[item.id] also.
And initial declaration is
var newPermissionArr = [];
var staticArr = [];
where for eg item is
{
roleId : 1,
permissions : [{"name": "A", "id" : 1},{ "name" : "B", "id" : 2 }]
}
I need initial object Array to remain same and at the end i need to compare the initial array with the modified array and need to find the reference however on updating the status it updates in both array. How to avoid this ?

The arrays reference the same object. To modify just one of them, you should use slice() function for clone the array:
newpermissionArr[item.id] = vm.initialPermissionArr[item.id].slice();

This is happening because of following line of code
newpermissionArr[item.id] = vm.initialPermissionArr[item.id];
Here object is passed by reference, so whenever newpermission is updated intialpermission will also be updated.
To fix this just copy the intialPermissionArr to newPermissionArr.
Unfortunately,plain javascript does not have any function like angular.copy. So you will have to do this in following way-
newrPermissionArr[item.id] = JSON.parse(JSON.stringify(vm.intialPermissionArr[item.id]));
this should fix your problem.

When you assign something to a and b and it is a pointer in memory to object c. Then as soon as you change it to c2 both a and b will get c2 from that point as they were just pointers to same location.

JavaScript: Access object variable inside nested array

How would I access ArrayObjectVariable inside
ArrayObject[0]? I know if you don't have a [ ] around it its as simple
as ArrayObject[0].ArrayObjectVariable?
var ArrayObjectVariableValue = 'AyOhVeeVee';
var ArrayObject = []
ArrayObject[0] = [{ ArrayObjectVariable : ArrayObjectVariableValue }];
alert(ArrayObject[0]???);
I didn't realize the whole "ArrayObject[0][0].ArrayObjectVariable" thing. Thanks for the replies. I was trying it with just one ("[0]") instead of two ("[0][0]"). My second question is, what is the second "[0]" for? I just tried making multiple variables and it still used "[0][0]" ? So what's the second "[0]" controlling?
Third question? I noticed that it created a variable outside the array when I did that? When I change the value of the variable in the array, it has no effect on the one outside of it? Likewise, when I change the value of the variable outside of the array it has no effect on the one inside it. Is there a way to create the array without creating a variable outside of the array with the same name? Thanks :)
OK figured it out :) Just make the Object in the array without the "[ ]". The whole point of this was to figure out how to access nested items but I got it now. Didn't realize how to make them without the "[ ]". Example for those of you struggling like I was:
// create variables that we are going to use in Array Objects. Or make a function with the values.
var ATV1 = 'AyTeeVeeOne', ATV2 = 'AyTeeVeeTwo', ANV1 = 'AyEnVeeOne';
var ATV3 = 'AyTeeVeeThree', ATV4 = 'AyTeeVeeFour', ANV2 = 'AyEnVeeTwo';
// Make an Array
var ArrayObject;
ArrayObject = [{}];
// Insert variables into Array object(s).
ArrayObject[0] = {ArrayTestObject1 : { ArrayTestValue1:ATV1,
ArrayNestedObject1:{ ArrayNestedValue1:ANV1 },
ArrayTestValue2:ATV2
}};
ArrayObject[1] = {ArrayTestObject2 : { ArrayTestValue3:ATV3,
ArrayNestedObject2:{ ArrayNestedValue2:ANV2 },
ArrayTestValue4:ATV4
}};
// Access Array Object Variables
alert(ArrayObject[0].ArrayTestObject1.ArrayTestValue1) // Example 1
alert(ArrayObject[1].ArrayTestObject2.ArrayNestedObject2.ArrayNestedValue2) // Example 2

ArrayObject[0][0].ArrayObjectVariable
You have an array for the value of ArrayObject[0], so treat it like any other array.

use this:here you have ArrayObject as array and you are creating index as zero to the array and in that on zeroth place ArrayObjectVariable key resides.
<script>
var ArrayObjectVariableValue = 'AyOhVeeVee';
var ArrayObject = []
ArrayObject[0] = [{
ArrayObjectVariable : ArrayObjectVariableValue }];
alert(ArrayObject[0][0].ArrayObjectVariable);
</script>

Can I find an object by the value of one of its properties?

I've got a mother object filled with objects that looks like this:
profiles[ slug ] = {
slug : slug,
url : url,
el : $('#' + el),
position : this.el.position().left
};
I want to be able to reference an object in this array by its position property. Is there any quick way of doing this, save for iterating over all of them and comparing each object's value to what I'm searching for?

Underscore.js has a lot of utilities that help with these types of lookups: http://underscorejs.org/#findWhere
Example code:
var result = _.findWhere(profiles, {position: SEARCH_VALUE});

Is there any quick way of doing this, save for iterating over all of them
Yes: you can build/maintain a secondary index where the key is the position and the value is the object.
index = {};
for (slug in profile) {
if (profile.hasOwnProperty(slug)) {
index[profile[slug].position] = profile[slug];
}
}

OOP get this key value of object array

So close to nailing this but falling at the last hurdle... Need some clarification.
Basically, I want to load in the array value of a key in a given object as a variable, if other variable strings match.
Perhaps it's better if I give it some context:
js:
var ArraysObject = {
"new" : [
"http://productPageBanners/UK/2new/c0bkn201001u0000.jpg",
"http://productPageBanners/UK/2new/h0ihd60100000001.jpg",
"http://productPageBanners/UK/2new/l0flj20100000001.jpg",
"http://productPageBanners/UK/2new/m0lrt60100000001.jpg",
"http://productPageBanners/UK/2new/p0gps50106000001.jpg"
],
"knives" : [
"http://productPageBanners/UK/3aknives/c0bkn201001u0000.jpg",
"http://productPageBanners/UK/3aknives/n01pl20100000001.jpg"
]
};
var url = jQuery(location).attr('href'); // get the current url, outputs URL
var icatRef = url.split("/")[4]; // capture the icatRef from url, outputs ==>"knives"
// Get properties on the object ArraysObject as an array
var icatTitlesInObject = Object.keys(ArraysObject); // outputs the keys in object, i.e ==> ["new","knives"]
Then I want to check that if the indexOf that array is equal to the icatRef (pulled from the URL), then create a new variable which stores the relevant array from the correct key.
Something like:
if (icatsArray.indexOf() == icatRef) {
var currentarraytorandomise = ArraysObject.keys.this};
// if "knives" is the icatRef then currentarraytorandomise ==> [
// "http://productPageBanners/UK/3aknives/c0bkn201001u0000.jpg",
// "http://productPageBanners/UK/3aknives/n01pl20100000001.jpg"
// ]
However that last bit is wrong because currentarraytorandomise is undefined.
I hope that's clear! Quite new to OOP.

You're using indexOf incorrectly, try something like this:
var currentarraytorandomise, index = icatsArray.indexOf(icatRef);
if (index >= 0) {
currentarraytorandomise = ArraysObject[icatsArray[index]];
}
But you could just try to get the array directly:
ArraysObject[icatRef]
Without extracting keys or anything. If icatRef doesn't exist, you'll get undefined.