How to convert JS object data to x-www-form-urlencoded

Question

I wish to convert a JS object into x-www-form-urlencoded. How can I achieve this in angular 2?

export class Compentency {
  competencies : number[];
}
postData() {
        let array =  [1, 2, 3];
        this.comp.competencies = array;
        let  headers = new Headers({ 'Content-Type': 'application/x-www-form-urlencoded' });
        let options = new RequestOptions({ headers: headers, method: 'post' });
        return this.http.post(this.postUrl, JSON.stringify(this.comp), options)
        .map(res => res.json().data.competencies)
        .catch(this.handleError);
    }

Answer 1

let o = { a:1, b:'2', c:true };
let s = new URLSearchParams(Object.entries(o)).toString();
console.log(s); 

Answer 2

Assume have an object named postdata as below:

const postdata = {
  'a':1,
  'b':2,
  'c':3
};

and, you want convert it into x-www-form-urlencoded format, like: a=1&b=2&c=3

with URLSearchParams it's very easy to do it.

const rawData = new URLSearchParams(Object.keys(postdata).map(key=>[key,postdata[key]]));
console.log(rawData.toString());//a=1&b=2&c=3