Js push value to object array

Question

i have the following object array

 datasets: [{
 data: [],
 backgroundColor: [
 "#FF6384",
 "#4BC0C0",
 "#FFCE56",
 "#E7E9ED",
 "#36A2EB"
 ],
 label: 'My dataset' // for legend
}],
labels: []
};

and i have another object array like bellow

[
{
"PORT": "MY",
"Country Name": "AUSTRALIA",
"nocontainers": "1017"
},
{
"PORT": "MY"
"Country Name": "CAMBODIA",
"nocontainers": "1"
},
{
"PORT": "DE"
"Country Name": "CHINA",
"nocontainers": "13846"
},
{
"PORT": "DE"
"Country Name": "HONG KONG",
"nocontainers": "252"
},
{
"PORT": "MY"
"Country Name": "INDONESIA",
"nocontainers": "208"
}

what i want to is to push all the value from 'nocontainers' to 'data' key and value from 'Country Name' to 'labels' key in first array.

i have tried array.push but didn't work, my final array should look like bellow

 datasets: [{
 data: [1017, 1, 13846, 252, 208],
 backgroundColor: [
 "#FF6384",
 "#4BC0C0",
 "#FFCE56",
 "#E7E9ED",
 "#36A2EB"
 ],
 label: 'My dataset' // for legend
}],
labels: ["AUSTRALIA (MY)","CAMBODIA (MY)","CHINA (DE)","HONG KONG (DE)","INDONESIA (MY)"]
};

Answer 1

You can create your object using .map with destructuring assignment to pull out the required properties from your countries object.

See working example below:

const countries = [{PORT:"MY","Country Name":"AUSTRALIA",nocontainers:"1017"},{PORT:"MY","Country Name":"CAMBODIA",nocontainers:"1"},{PORT:"DE","Country Name":"CHINA",nocontainers:"13846"},{PORT:"DE","Country Name":"HONG KONG",nocontainers:"252"},{PORT:"MY","Country Name":"INDONESIA",nocontainers:"208"}];
const obj = {
 datasets: {
 data: [],
 backgroundColor: ["#FF6384", "#4BC0C0", "#FFCE56", "#E7E9ED", "#36A2EB"],
 label: 'My dataset'
 },
 labels: []
};
obj.datasets.data = countries.map(({nocontainers: nc}) => +nc);
obj.labels = countries.map(({"Country Name": cn, PORT: p}) => `${cn} (${p})`);
console.log(obj);

• Shidersz: Note that he wanted to change original object, maybe you should provide an alternative example: obj.datasets.data = countries.map(...) and obj.labels = countries.map(...). Anyway +1!
• Elite user: what if i want to combined new port value to country object in brackets?
• Nick Parsons: @Eliteuser I don't really understand your question. Pease edit your question (leaving the original untouched) with your updated question, providing the expected output.
• Nick Parsons: @Shidersz thanks, I decided to change my original answer :)
• Elite user: @NickParsons sorry about that. i was just thinking what is i want to 'PORT' value to be displayed in front of in new array like this labels: ["AUSTRALIA (MY)","CAMBODIA (MY)","CHINA (DE)","HONG KONG (DE)","INDONESIA (MY)"]

Answer 2

let data = {
 datasets: {
 data: [],
 backgroundColor: [
 "#FF6384",
 "#4BC0C0",
 "#FFCE56",
 "#E7E9ED",
 "#36A2EB"
 ],
 label: 'My dataset' // for legend
 },
 labels: []
}
let arr = [{
 "Country Name": "AUSTRALIA",
 "nocontainers": "1017"
 },
 {
 "Country Name": "CAMBODIA",
 "nocontainers": "1"
 },
 {
 "Country Name": "CHINA",
 "nocontainers": "13846"
 },
 {
 "Country Name": "HONG KONG",
 "nocontainers": "252"
 },
 {
 "Country Name": "INDONESIA",
 "nocontainers": "208"
 }
]
arr.forEach(a => {
 data.datasets.data.push(a['nocontainers'])
 data.labels.push(a['Country Name'])
})
console.log(data)