Develop Reference

How to Turn a Multiple Array Object into Query String Parameters in JavaScript

I have the following object below with multiple arrays.
{
"services": [
{
"id": "100",
"name": "PIX"
},
{
"id": "200",
"name": "Rendimentos"
}
],
"channels": [
{
"id": "300",
"name": "Chat"
}
]
}
The idea is to generate query strings, something like that.
services=100&services=200&channels=300
I know you can do it with map and join, but I would know if it was with a pure object, now this format below, I'm confused

You can use URLSearchParams() API.
Iterate your data and append key/value pairs or map an entries array to pass to the constructor
I have no idea what determines the expected output you have shown from the data displayed so am using a simpler data structure for demonstration purposes.
You can combine with URL() API to create full url string as shown below also
const data = [
{name:'foo', value:10},
{name:'bar', value:20}
]
// Loop and append key/values
const params = new URLSearchParams();
data.forEach(e => params.append(e.name, e.value));
console.log('params:', params.toString());
// Alternate approach passing entries array to constructor
const params2 = new URLSearchParams(data.map(e => [e.name,e.value]));
console.log('params2:',params2.toString())
//Adding to a URL
const url = new URL('http://example.com')
url.search = params
console.log('Full url:',url)
Using the updated array data in question:
const data={services:[{id:"100",name:"PIX"},{id:"200",name:"Rendimentos"}],channels:[{id:"300",name:"Chat"}]};
const entries = [];
Object.entries(data).forEach(([k,arr])=> arr.forEach(({id}) => entries.push([k,id])));
const params = new URLSearchParams(entries);
const url = new URL('http://example.com')
url.search = params;
console.log(url)

Looks like you're hung up on trying to iterate an object with map() or join(), which you can't do directly. Instead you can use Object.entries to convert the object into an array and iterate that. Since there is a nested map() you can flat() it before join()
let obj = {
"services": [{
"id": "100",
"name": "PIX"
},
{
"id": "200",
"name": "Rendimentos"
}
],
"channels": [{
"id": "300",
"name": "Chat"
}]
}
let queryString = Object.entries(obj).map(s => s[1].map(e => `${s[0]}=${e.id}`)).flat().join('&')
console.log(queryString)

How to create JSON format dictionary?

I would like to format my data with a key to access the information. This is what I currently have:
const dict = [];
dict.push({"student": "Brian", "id":"01", "grade":"Sophomore"})
return dict;
Output:
{
"student":"Brian"
"id": "01",
"grade": "Sophomore"
}
However, I am interested in creating this type of format with my data:
{
"student":"Brian" [
{
"id":"01",
"grade": "Sophomore"
}
]
}
How would I be able to do so? I would like to use "student" as my key to access the rest of its information associated.

You're basically there. However objects always need keys to go along with the values, so you need to assign a key to the object you want to create
const dict = [];
dict.push({
"Brian": {
"id": "01",
"grade": "Sophomore"
}
})
// to retrieve:
let brian = dict.filter(e=>Object.keys(e)[0]==="Brian").flatMap(Object.values)
if (brian && brian.length>0) console.log(brian[0])
//You could also set up your `dict` like this:
const dict2 = {};
dict2["Brian"] = {
"id": "01",
"grade": "Sophomore"
};
//and that would allow you to retrieve your object with
brian = dict2.Brian;
console.log(brian)

Access object inside the array which is inside the other object

I have an array of objects, where inside each object I have another array. I need to access the object inside that array. How do I do that?
As an example, here is my function where I log into the console each one of those arrays. And I want to console log each description instead.
const var = data.filter((u) => {
console.log(u.array)
})
And here is the JSON data
[
{
"agreed": true,
"email": "test#test.com"
"array": [
{
"name": "Alex",
"city": "Pedro",
"state": "WA",
"description": "Alex was very patient. He is one of the good guys!"
}
]
}
]

Here is the code snippet. data contains the original array then u contains each object of outer array. Then u.array.map traverses each individual array and i.description contains each sub-array's description.
data.map((u) => {
u.array.map((i) => {
console.log(i.description);
}
})

if you know the exact index, you can do this.
const var = data.filter((u) => {
console.log(u.array[0].description)
})
if you dont know the exact index, or if you wanna do this for each item in the array you can do this.
const var = data.filter((u) => {
u.array.forEach(item => {
console.log(item.description)
})
})

Well,
if this would be the structure of your Javascript Object
var data =
[
{
"agreed": true,
"email": "test#test.com"
"array": [
{
"name": "Alex",
"city": "Pedro",
"state": "WA",
"description": "Alex was very patient. He is one of the good guys!"
}
]
}
]
Then You can access the array by,
data[0].array[0].name;
And you can console.log description like this, if you are using jquery
$.each(data[0].array, function(i,v){
console.log(v.description);
})

You index into arrays with array[someIndex] starting with 0 for the first item.
So you can:
let arr = [{
"agreed": true,
"email": "test#test.com",
"array": [{
"name": "Alex",
"city": "Pedro",
"state": "WA",
"description": "Alex was very patient. He is one of the good guys!"
}]
}]
// get the first whole object
console.log(arr[0])
// get the arra property of the first object
console.log(arr[0].array)
// get the first object of that array
console.log(arr[0].array[0])
// get a property on that object
console.log(arr[0].array[0].name)
If you need to dig into an array and access of manipulate values, you can use tools like forEach, reduce(), etc. to loop over them:
let arr = [{"agreed": true,"email": "test#test.com","array": [{"name": "Alex","city": "Pedro","state": "WA","description": "Alex was very patient. He is one of the good guys!"},{"name": "Mark","city": "Anchorage","state": "AK","description": "Mark is also patient. He is one of the good guys!"}]},{"agreed": true,"email": "test#test.com","array": [{"name": "Steve","city": "New York","state": "NY","description": "Steve was very patient. He is one of the good guys!"},{"name": "Nancy","city": "Anchorage","state": "AK","description": "Nancy is also patient. She is awesome!"}]}]
// log each name
arr.forEach(obj => {
obj.array.forEach(item => {
console.log(item.name)
})
})
// build a new list of just the cities
let cities = arr.reduce((arr, obj) => {
obj.array.forEach(item => {
arr.push(item.city)
})
return arr
}, [])
console.log(cities)

You can save all descriptions to an array or just display it, like this
let descriptions = [];
data.map(item => item.array)
.forEach(array => {
array.forEach(obj => {
console.log(obj.description);
descriptions.push(obj.description);
});
});
console.log(descriptions);

Converting JSON/JS Object to array

I have a JSON response from my API that is structured like so:
{
"data": [
{
"id": "1", "name": "test"
},
{
"id": "2", "name": "test2"
}
]
}
When I reference data I get the array with each record. I need the curly braces to be brackets due to a plugin I am using requiring it to be an array.
Desired output:
[
["1", "test"],
["2", "test"]
]
How can I convert the above JSON to this?
Edit:
This turned out to be a problem with a plugin I was using, and I knew how to do this fine all along. Thought I was going crazy but my code was fine, some plugin was screwing things up.

You can do this using Array.prototype.map
var arr = json.data.map(function(x){
return [x.id, x.name];
});

Something like this maybe: http://jsfiddle.net/3gcg6Lbz/1/
var arr = new Array();
var obj = {
"data": [
{
"id": "1", "name": "test"
},
{
"id": "2", "name": "test2"
}
]
}
for(var i in obj.data) {
var thisArr = new Array();
thisArr.push(obj.data[i].id);
thisArr.push(obj.data[i].name);
arr.push(thisArr);
}
console.log(arr);

Loop over JSON items whether JSON object has multiple arrays or not

I have a working version of a function to loop through a single array in a JSON object, e.g.
[{
"Name": "John",
"Surname": "Johnson"
}, {
"Name": "Peter",
"Surname": "Johnson"
}]
sample function:
function FindName(NameToFind, data1) {
objData = JSON.parse(data1);
for (var i = 0; i < objData.length; i++) {
var Name = objData[i].Name;
if (Name == NameToFind) {
alert("found!");
}
}
}
Now I need to change this function to allow for either single OR multiple arrays e.g.
{
"Table1": [{
"Name": "John",
"Surname": "Johnson"
}, {
"Name": "Peter",
"Surname": "Johnson"
}],
"Table2": [{
"Name": "Sarah",
"Surname": "Parker"
},
{
"Name": "Jonah",
"Surname": "Hill"
}
]
}
Is there a way to determine whether the object has 1 array (like in first example) or more than one arrays (like in 2nd example), and any advice/guidance on how to extend the function to be able to loop through all the items whether it has 1 array or multiple arrays?

Your first object is an array, the second one isn't.
You can test if your argument is an array, or even just test
if (objData[0]) // that's an array
EDIT :
if you want to iterate over all properties of a (just json decoded) object, when it's not an array, you can do this :
for (var key in objData) {
var value = objData[key];
// now use the key and the value
// for example key = "Table1"
// and value = [{"Name":"John","Surname":"Johnson"}, ... ]
}