Develop Reference

Function returning object instead of Array, unable to .Map

I'm parsing an order feed to identify duplicate items bought and group them with a quantity for upload. However, when I try to map the resulting array, it's showing [object Object], which makes me think something's converting the return into an object rather than an array.
The function is as follows:
function compressedOrder (original) {
var compressed = [];
// make a copy of the input array
// first loop goes over every element
for (var i = 0; i < original.length; i++) {
var myCount = 1;
var a = new Object();
// loop over every element in the copy and see if it's the same
for (var w = i+1; w < original.length; w++) {
if (original[w] && original[i]) {
if (original[i].sku == original[w].sku) {
// increase amount of times duplicate is found
myCount++;
delete original[w];
}
}
}
if (original[i]) {
a.sku = original[i].sku;
a.price = original[i].price;
a.qtty = myCount;
compressed.push(a);
}
}
return compressed;
}
And the JS code calling that function is:
contents: compressedOrder(item.lineItems).map(indiv => ({
"id": indiv.sku,
"price": indiv.price,
"quantity": indiv.qtty
}))
The result is:
contents: [ [Object], [Object], [Object], [Object] ]
When I JSON.stringify() the output, I can see that it's pulling the correct info from the function, but I can't figure out how to get the calling function to pull it as an array that can then be mapped rather than as an object.
The correct output, which sits within a much larger feed that gets uploaded, should look like this:
contents:
[{"id":"sku1","price":17.50,"quantity":2},{"id":"sku2","price":27.30,"quantity":3}]
{It's probably something dead simple and obvious, but I've been breaking my head over this (much larger) programme till 4am this morning, so my head's probably not in the right place}

Turns out the code was correct all along, but I was running into a limitation of the console itself. I was able to verify this by simply working with the hard-coded values, and then querying the nested array separately.
Thanks anyway for your help and input everyone.

contents: compressedOrder(item.lineItems).map(indiv => ({
"id": indiv.sku,
"price": indiv.price,
"quantity": indiv.qtty
}))
In the code above the compressedOrder fucntion returns an array of objects where each object has sku, price and qtty attribute.
Further you are using a map on this array and returning an object again which has attributes id, price and quantity.
What do you expect from this.

Not sure what exactly solution you need but I've read your question and the comments, It looks like you need array of arrays as response.
So If I've understood your requirement correctly and you could use lodash then following piece of code might help you:
const _ = require('lodash');
const resp = [{key1:"value1"}, {key2:"value2"}].map(t => _.pairs(t));
console.log(resp);
P.S. It is assumed that compressedOrder response looks like array of objects.

Javascript ForEach on Array of Arrays

I am looping through a collection of blog posts to firstly push the username and ID of the blog author to a new array of arrays, and then secondly, count the number of blogs from each author. The code below achieves this; however, in the new array, the username and author ID are no longer separate items in the array, but seem to be concatenated into a single string. I need to retain them as separate items as I need to use both separately; how can I amend the result to achieve this?
var countAuthors = [];
blogAuthors = await Blog.find().populate('authors');
blogAuthors.forEach(function(blogAuthor){
countAuthors.push([blogAuthor.author.username, blogAuthor.author.id]);
})
console.log(countAuthors);
// Outputs as separate array items, as expected:
// [ 'author1', 5d7eed028c298b424b3fb5f1 ],
// [ 'author2', 5dd8aa254d74b30017dbfdd3 ],
var result = {};
countAuthors.forEach(function(x) {
result[x] = (result[x] || 0) + 1;
});
console.log(result);
// Username and author ID become a single string and cannot be accessed as separate array items
// 'author1,5d7eed028c298b424b3fb5f1': 15,
// 'author2,5dd8aa254d74b30017dbfdd3': 2,
Update:
Maybe I can explain a bit further WHY on what to do this. What I am aiming for is a table which displays the blog author's name alongside the number of blogs they have written. However, I also want the author name to link to their profile page, which requires the blogAuthor.author.id to do so. Hence, I need to still be able to access the author username and ID separately after executing the count. Thanks

You could use String.split().
For example:
let result = 'author1,5d7eed028c298b424b3fb5f1'.split(',')
would set result to:
['author1' , '5d7eed028c298b424b3fb5f1']
You can then access them individually like:
result[1] //'5d7eed028c298b424b3fb5f1'

Your issue is that you weren't splitting the x up in the foreach callback, and so the whole array was being converted to a string and being used as the key when inserting into the results object.
You can use array destructuring to split the author name and blog id, and use them to optionally adding a new entry to the result object, and then update that result.
countAuthors = [
['author1', 'bookId1'],
['author2', 'bookId2'],
['author1', 'bookId3'],
['author1', 'bookId4'],
['author2', 'bookId5']
]
var result = {};
countAuthors.forEach(([author, id]) => {
if (result[author] === undefined) {
result[author] = {count: 0, blogIds: []};
}
result[author].count += 1;
result[author].blogIds.push(id);
});
console.log(result);

Add element to multi row array with angular / javascript

I have the following array with data:
[
{"count":1,"title":"Ark: Survival","platform":"Playstation PS4"},
{"count":2,"title":"Lara Croft:", "platform":"Playstation PS4"},
{"count":1,"title":"Madden NFL", "platform":"Playstation PS4"}
]
All in my angular Cart scope:
var data = $scope.cart;
now i would like to add to each row the order number, so i use a push:
$scope.cart.push({"orderNumber": $scope.OrderNumber});
the problem is that is adds the order number but as a separate row and not inside each of the rows. so my desired output should look like this:
[
{"count":1,"title":"Ark: Survival","platform":"Playstation PS4","orderNumber":1 },
{"count":2,"title":"Lara Croft:", "platform":"Playstation PS4","orderNumber":1},
{"count":1,"title":"Madden NFL", "platform":"Playstation PS4","orderNumber":1}
]
how would i push to each row of the array? i tried several versions but can't seem to get it to work.

in order to achieve that you should iterate through each object and set order number separately
angular.forEach($scope.cart, function (value, key) {
value.orderNumber = $scope.OrderNumber;
});

You need to iterate over each item and add the orderNumber as a property for each item. So you can use forEach function of the angular for that.
angular.forEach($scope.cart, (item) => item.orderNumber = $scope.OrderNumber)

just got an answer that i implemented but the user has deleted the response, however it works perfect, this was the solution that i used:
$scope.cart.forEach(item => item.orderNumber = $scope.OrderNumber)

ng-repeats, showing record while it's value is a part of field of another object

I've got objects 'ing' with a field named 'id' and another one called 'fObj' with a field named 'contain'.
By using ng-repeat i'd like to show only these 'ing' objects where ing.id is a part of fObj.contain
e.g.
ing=[{id: 1,field: value},{id:2, field: othervalue},{id:3, field: cat}];
fObj={field1: value1, field: value2, contain: ':1:3:'};
By having this contain value I'd like to show only ing's with id=1 and id=3
Yeah, I know there are two types of data (number and string) but even if i changed numbers to strings it still didn't work
I just dont't know how to make it works. It's probably some kind of custom filter, but I've tried couples and nothing happend.
I would be glad if you suggest me a solution.
Thanks

In your controller,
var ids = fObj.contain.split(':');
// the array for your ng-repeat
var displayIng = [];
// loop the objects, see if the id exists in the list of id's
// retrieved from the split
for(i = 0; i < ing.length; i++) {
if(ids.indexOf(ing.id.toString()) displayIng.push(ing[i]);
}

I would split the numbers out of fObj.contain; and use them as hashmap object keys for simple filtering of the array
var ing=[{id: 1},{id:2},{id:3}];
var fObj={contain: ':1:3:'};
var IDs = fObj.contain.split(':').reduce(function(a,c){
a[c]=true;
return a;
},{});
// produces {1:true,3:true}
var filtered = ing.filter(function(item){
return IDs[item.id];
});
console.log(filtered)

How to push object to array in angularjs?

This is my code
$scope.studentDetails=[];
$scope.studentIds={};
$scope.studentIds[0]{"id":"101"}
$scope.studentIds[1]{"id":"102"}
$scope.studentIds[2]{"id":"103"}
in the above code when i select student id:101 i got marks from services like
$scope.studentMarks={};
$scope.studentMarks[0]{"marks":"67"}
$scope.studentMarks[1]{"marks":"34"}
next i select student id:102 i got marks from services like
$scope.studentMarks={};
$scope.studentMarks[0]{"marks":"98"}
$scope.studentMarks[1]{"marks":"85"}
finally i want to store student details in to one array like
$scope.studentDetails=[{"id":"101","marks":[67,34]},{"id":"102","marks":[98,85]}]
using angularjs.

Seems like its more of a JS question than angular.
What about the Javascript push method?
$scope.studentDetails.push({id: 101, marks: [67, 34]});

You can use Array.push to add one object, or concat, to concat array into another array. See the references.

angularJS is just a library to extend Javascript. You push into an array just like you would any object in Javascript.
First off, you need to declare an array.
$scope.studentIds = []; // Array of student ids.
Then when you want to add, you push:
$scope.studentIds.push({id: "101"});

To do this naively you need to loop through the student ids and then loop through the marks object and adding it to your studentDetails object if the ids match:
var studentDetails = [];
for (var id in studentIds) {
var studentDetail = {}; // this will be a single student
var marks = [];
if (studentIds.hasOwnProperty(id)) {
for (var mark in studentMarks) {
if (studentMarks.hasOwnProperty(mark) && mark.id === id) {
studentDetail.id = id;
marks.push(mark.marks);
}
}
studentDetail.marks = marks;
}
studentDetails.push(studentDetail);
}
$scope.studentDetails = studentDetails;