JavaScriptでJSONからクエリパラメータを生成する

const params = new URLSearchParams({ x: 100, y: 50 });
console.log(params.toString()); // "x=100&y=50"

const params = new URLSearchParams({ x: 100, y: 50 });
const url = 'http://localhost';
const fullUrl = (url + '?' + params);
console.log(fullUrl); // "http://localhost?x=100&y=50"