Simple url to json and json to url converter

urlJsonconverter.js

function jsToUrl(js) {
  return [""]
    .concat(Object.keys(js))
    .reduce((accumulator, key, i) => {
      return `${accumulator}&${key}=${encodeURIComponent(js[key])}`;
    })
    .replace(/^&/, "?");
}

function urlToJs(url) {
  return JSON.parse(
    "{" +
      url
        .replace(/^\?/, "")
        .split("&")
        .map(item =>
          item.replace(
            /^(.+?)=(.*)$/,
            (a, key, value) =>
              `"${key}":"${decodeURIComponent(value).replace(/"/g, '\\"')}"`
          )
        )
        .join(",") +
      "}"
  );
}

const json = {
  foo: 12345677654,
  bar: "buuuzzzzz",
  foobar: true,
  string: 'I am a "custom" string'
};
console.log(jsToUrl(json));

console.log(
  urlToJs(
    "?foo=12345677654&bar=buuuzzzzz&foobar=true&string=I%20am%20a%20%22custom%22%20string"
  )
);
console.log(
  urlToJs(
    "foo=12345677654&bar=buuuzzzzz&foobar=true&string=I%20am%20a%20%22custom%22%20string"
  )
);
console.log(
  urlToJs(
    "foo=12345677654&bar=buuuzzzzz&foobar=true&empty=&string=I%20am%20a%20%22custom%22%20string"
  )
);