Remove outer array containing arrays with objects, javascript [closed] - javascript

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I'm getting back an array which looks like this:
[ {...}, {...}, {...} ]
I can get it to look like this with map():
[ [{...}], [{...}], [{...}] ]
I am having trouble getting this result:
[{...}], [{...}], [{...}]
I just need to remove the outer/parent array. I have tried flatten, flattenDepth, and reduce, however, I can't seem to figure out what I am doing wrong.

The format you're asking for as output is a bunch of arrays with no containing object or array. That's not a thing you can do, at least not in one variable. The middle example is probably just fine for whatever you're using it for -- you can use forEach to handle each inner array element separately.

You can just loop an you will get what you want
Example:
const arr = [
[{}],
[{}],
[{}]
]
console.log(arr.map(el => ` This an array of object ===> ${el}`))

Maybe take a look at the ES6 spread operator, it looks somewhat like what you're asking for. Be aware that it might not be widely supported though.
You could also try function.apply, that takes a this object (which can be null) and an array with arguments and calls a function with them (if that's what you need).

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JSON structure in javascript [closed]

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I am trying to create a javascript structure that looks like that:
[{'red': {color:'red},...}]
starting with an array of colors:
const COLORS = ['red','yellow']
This is what I have tried:
const finalArray = COLORS.map(color => ({ [color]: { color } }))
However this produces an array that looks like that:
[{red: {color:'red'}}]
instead of [{'red': {color:'red'}}]
Which is not the same and will prevent the library I am using from understanding the array.
Any idea is welcome.
I edited the question since there where some typos. Hope it’s clearer now.
Thanks
What are the differences between:
[{red: {color:'red'}}]
// and
[{'red': {color:'red'}}]
If it's only a quote related matters, you can do like:
COLORS.map(color => ({ [`'${color}'`]: { color } }));
These are just two ways of representing the same array/object. If you need a string containing the canonical representation of the array/object (with double quotes around the names of the properties), you can use JSON.stringify(finalArray).
Please note this will quote ALL your property names, like in:
[{"red":{"color":"red"}}]
And please note the above is a string, as if you did:
finalString = '[{"red":{"color":"red"}}]'
(Note: this question has been closed, and I agree it's not clear enough. But it's quite evident that the user is confusing the internal structure of an array/object with its external representation, and with the way the array/object is shown by a development environment, browser, etc. As this is a very common problem, mostly in new programmers or newcomers to a tool, the question and the answers may still be helpful.)

How to get data in object without looping [closed]

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I want to get data from the object without for loop
this is my object
data = [{name:"A",value:[java:45,c++:50]},{name:"B",value:[java:12,c++:47]},{name:"C",value:[java:15,c++:32]}]
Expected result:
result_name = ["A","B","C"]
result_java = [45,12,15]
The structure of your array data is invalid. You wrote nested array value in square brackets yet the items are written as key-value pairs.
There is no magical way you can obtain multiple data from an array without iteration/looping. (unless you already know the indices, but this defeats the purpose of using arrays)
That said, if you meant to avoid only the "for" loops, you can:
Fix your data as below.
let data = [
{name:"A", value:{java:45,"c++":50}},
{name:"B", value:{java:12,"c++":47}},
{name:"C", value:{java:15,"c++":32}}
];
Run an alternative loop such as below.
console.log(data.map(item => item.name)); // ["A", "B", "C"]
console.log(data.map(item => item.value.java)); // [45,12,15]

value extraction from array in javascript [closed]

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business=[0:{"name":{"en":'prateek'}},1:{"name":{"ar":'rahul'}}]
How I can extract the value of en and ar from this type of the repeted object in a array
The issue with your question is that you define business as an Array with the use of square brackets, but then proceed to use key value pairs directly within the array (via the usage ":"), which is reserved for objects and not arrays. I'd recommend researching both array and object datatypes, however simply put:
let myArray = [1, 2, 3, ...];
// only stores values which can be retrieved using the values index i.e. myArray[0]
let myObj = {"key1" : "value1", "key2" : "value2"};
// values are stored against keys, and can be accessed via the key i.e. myObj.key1
I think you've confused how objects and arrays should work. My guess is that you'd be better off with this structure:
let businesses = [];
businesses.push({enName: 'prateek', arName: 'rahul'});
console.log(businesses[0], businesses[0].enName, businesses[0].arName);
This way you're using an array to hold a collection of businesses and which are represented by objects. These objects in turn have attributes for enName and arName.
I think this would be a much clearer way of structuring your issue.

Copy first 7 keys in object into a new object [closed]

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As the title suggests, how do I make a new object containing the 7 first keys of another object using JS? :) This is the structure of the object I would like to copy the data from.
{"data":[{"id":2338785,"team1":{"id":10531,"name":"Just For Fun"},"team2":{"id":10017,"name":"Rugratz"},"result":"2 - 0","event":{"name":"Mythic Cup 5","id":5148},"format":"bo3","stars":0,"date":1578279271000},....],"last_update":1578329378792}
Let's say there are 100 keys like this one, and I only want to copy the 7 first ones into a new object in JS.
Well technically, you have only 2 keys in the given Object but if you mean the data object, here's what you can do.
const MyNewObject = Object.entries(YourObject)
const results = []
and a simple for loop
MyNewObject.forEach((pair,i) => {
// for the 8th item it breaks and doesn't push it to results array
if ( i === 7 ) break;
results.push(pair)
}
OR u use slice instead :
// a little bit neater , and u call remove the empty results array above
const thisNewResult = MyNewObject.slice(0,6)
and finally the results is an array of key value pairs and you should do this code to make a new object from the results entries
const finalResults = Object.fromEntries(results)
Please notice that this may not be the Order you want since Object.Entries gives you the same order as the order of for in loop (for more info visit Elements order in a "for (… in …)" loop)

Unusual array with key value NaN property, containing more arrays? [closed]

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I have an unusual Javascript array with a length of 0, but if I expand the array I can see it contains multiple nested arrays with the same property, and eventually an Array containing an object. I've never seen this type of array / object before.
This is a sudo code version (as far I can read it):
[NaN: [{foo:'barr'}]]
But constructing an object like that would cause an error. Can anyone explain what it is?
This is a screen shot of what it looks like console logged in Chrome:
And console logged in Firefox:
It looks like, you have 'NaN' as key, which is possible (arrays are objects), because you may have calculated the index, which goes wrong.
var array = [];
array['x' * 3] = 'value'; // index/key is NaN
console.log(array);
console.log(array.NaN);

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