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How to array map instead of nested for loops

For my scenario, I need to push elements to an addresses array which contains objects. I'm working with vue.js.
My current working function is:
propagateCustomerInfo(selectedOption, id){
// Propagate addresses
this.addresses = selectedOption.addresses
// Propagate contact's addresses
for (var i = selectedOption.contacts.length - 1; i >= 0; i--) {
for (var j = selectedOption.contacts[i].addresses.length - 1; j >= 0; j--) {
let address = selectedOption.contacts[i].addresses[j]
address.contact = selectedOption.contacts[i]
this.addresses.push(address)
}
}
},
the selectedOption object has the below structure:
{
addresses: [
{
id: 0,
street: 'My street'
},
{...}
],
contacts: [
{
id: 0,
name: 'Lorem Ipsum',
addresses: [
{
id: 0,
street: 'My street'
},
{...}
],
}
]
}
Besides pushing every contact's address object to this.addresses array I need to append the contact to the address itself for multiselect rendering purposes. That's why I'm doing address.contact = selectedOption.contacts[i]
I almost sure that this can be accomplished in a prettiest way with some mapping/reduce combination but I can't figure out how to do it.
Any help will be really appreciated.
Thanks!

if you want to combine all address in contact variable to addresses variable:
this.contacts.map(contact => this.addresses.push(...contact.addresses))
Edit.
to inject the contact.id and contact.name:
this.contacts.map(contact => {
let temp = []
contact.addresses.map(address => {
temp.push({
name: contact.name,
id: contact.id,
...address
})
})
this.addresses.push(...temp)
})

How to change index and value of array object in javascript

I have this Javascript Object as below format but I want to convert it to another format as below:
I've pass value form let data = $('#clientForm').serializeArray();
Original format
let data = $('#clientForm').serializeArray();
{ name="addr_types", value="RESID"}
Wanted Format
{addr_types:"RESID"}
Or another format
{"addr_types":"RESID"}

Assuming a valid object, you could just assign the wanted property with the given key/value pair.
var source = { name: "addr_types", value: "RESID" },
target = {};
target[source.name] = source.value;
console.log(target);
ES6 with computed property
var source = { name: "addr_types", value: "RESID" },
target = { [source.name]: source.value };
console.log(target);

Given that your original object is a correct one
var original = {
name: "addr_types",
value: "RESID"
};
console.log(original);
var newName = original.name;
var newValue = original.value;
var newObject = {};
newObject[newName] = newValue;
console.log(newObject);

You can simply do it using .map() function. bellow is the example.
var original = [{
name: "addr_types",
value: "Work"
},{
name: "village",
value: "Vang Tobang"
},{
name: "commune",
value: "Tang Krasang"
},{
name: "destric",
value: ""
},{
name: "city",
value: "Com Pong Thom"
},{
name: "country",
value: "combodia"
},
];
newArray = original.map(function(item){
return {[item.name]: item.value}
});
If your data container is not array then you can simply create as like bellow.
newArray = [original].map(function(item){
return {[item.name]: item.value}
});
Here is the jsfiddle link: https://jsfiddle.net/kzrngch6/

Manipulate a key value pair to a string in Javascript

I need some help in manipulating a value pair array to return a string in a specific layout
This is the string i am trying to achieve:
'&test=id:1111|na:shoes|ca:shoe&test=id:2222|na:top|ca:tops'
This is the array I am trying to manipulate into my string
var prodlist =
[
{
name: 'shoe',
sku: '1111',
category: 'shoes'
},
{
name: 'top',
sku: '2222',
category: 'tops'
}
]
Here is what I have tried.
I added the 'deleteme' into the array thinking i could to a substitute later down the script.
function(){
var prods = prodlist;
var array = [];
for (var i = 0; i < prods.length; i++) {
var sku = (prods[i]['sku']);
var name = (prods[i]['name']);
var cat = (prods[i]['category']);
array.push({
deleteme: &test=id,
id: sku,
na: name,
ca: cat,
});
}
var newarray = array.toString();
return newarray;
}
At the moment this function returns '[object Object],[object Object]'
any help would be much appreciated.
Thanks

Quick and easy
function prods() {
var prods = prodlist;
var array = [];
for (let product of prods)
array.push('test=id:' + product.sku+ '|na:' + product.name + '|ca:' + product.category);
return '&' + array.join('&');
}

how about something like this?
var prodlist =
[{name: 'shoe',
sku: '1111',
category: 'shoes'},
{name: 'top',
sku: '2222',
category: 'tops'}]
var strTemplate = "&test=id:%sku%|na:%name%|ca:%category%"
prodlist.map( function(obj){
return strTemplate.replace(/%(\w+)%/g, function($1, $2) {
return obj[$2]
})
}).join('')
//returns
// "&test=id:1111|na:shoe|ca:shoes&test=id:2222|na:top|ca:tops"
or ES6 version (edited it down further as suggested by nnnnnn )
prodlist.map( obj => strTemplate.replace(/%(\w+)%/g, ($1, $2) => obj[$2])).join('')

New array of objects by comparing and pushing unique objects

I have 2 arrays of objects exclude and people, I want to create a new object by checking exclude properties against people properties and only adding objects in people that don't feature in exclude. So far my attempt is a little wild and wondering if someone can help make things a little better or offer a nicer solution?
Fiddle http://jsfiddle.net/kyllle/k02jw2j0/
JS
var exclude = [{
id: 1,
name: 'John'
}];
var peopleArr = [{
id: 1,
name: 'John'
}, {
id: 2,
name: 'James'
}, {
id: 3,
name: 'Simon'
}];
var myObj = [];
for (key in peopleArr) {
for (k in exclude) {
if (JSON.stringify(peopleArr[key]) != JSON.stringify(exclude[k])) {
console.log(peopleArr[key]);
myObj.push(peopleArr[key]);
}
}
}
console.log(myObj);

Under the assumption that exclude can have multiple items, I would use a combination of filter() and forEach() :
var newArray = peopleArr.filter(function(person) {
include = true;
exclude.forEach(function(exl) {
if (JSON.stringify(exl) == JSON.stringify(person)) {
include = false;
return;
}
})
if (include) return person;
})
forked fiddle -> http://jsfiddle.net/6c24rte8/

You repeat some JSON.stringify calls.
You can convert your arrays to JSON once, and then reuse it. Also, you can replace your push by Array.prototype.filter.
var excludeJson = exclude.map(JSON.stringify);
peopleArr = peopleArr.filter(function(x) {
return excludeJson.indexOf(JSON.stringify(x)) === -1;
});
Here is the working snippet:
var exclude = [{
id: 1,
name: 'John'
}];
var peopleArr = [{
id: 1,
name: 'John'
}, {
id: 2,
name: 'James'
}, {
id: 3,
name: 'Simon'
}];
var excludeJson = exclude.map(JSON.stringify);
peopleArr = peopleArr.filter(function(x) {
return excludeJson.indexOf(JSON.stringify(x)) === -1;
});
document.body.innerText = JSON.stringify(peopleArr);

This can be achieved with .filter and .findIndex
var myObj = peopleArr.filter(function(person){
var idx = exclude.findIndex(function(exc) { return person.id == exc.id && person.name == exc.name; });
return idx == -1; // means current person not found in the exclude list
});
I have explicitly compared the actual properties back to the original, there is nothing particularly wrong with your original way of comparing the stringified version (JSON.stringify(e) == JSON.stringify(x) could be used in my example)

Remove objects from array of object in javascript

I'm trying to remove objects from an array of object using a delta data i'm getting from server. I'm using underscore in my project.
Is there a straight forward way to do this, rather going with looping and assigning ?
Main Array
var input = [
{name: "AAA", id: 845,status:1},
{name: "BBB", id: 839,status:1},
{name: "CCC", id: 854,status:1}
];
Tobe Removed
var deltadata = [
{name: "AAA", id: 845,status:0},
{name: "BBB", id: 839,status:0}
];
Expected output
var finaldata = [
{name: "CCC", id: 854,status:1}
]

Try this
var finaldata = _.filter(input, function(item) {
return !(_.findWhere(deltadata, {id: item.id}));
});
It does assume that you have unique ID's. Maybe you can come up with something better.

Here's a simple solution. As others have mentioned, I don't think this is possible without a loop. You could also add checks for status and name in the condition, as this just compares IDs.
var finaldata = input.filter(function(o) {
for (var i = 0; i < deltadata.length; i++)
if (deltadata[i].id === o.id) return false;
return true;
});

A simple filter will do it:
var finaldata = _.filter(input, function(o) {
return _.findWhere(deltadata, o) === undefined;
});
A little more efficient than the findWhere would be creating a lookup map with ids to remove, and then filtering by that:
var idsToRemove = _.reduce(deltadata, function(m, o) {
m[o.id] = true;
return m;
}, {});
var finaldata = _.reject(input, function(o) { return o.id in idsToRemove; });