title: objectToQueryString tags: object,function,intermediate

Returns a query string generated from the key-value pairs of the given object.

Use Array.prototype.reduce() on Object.entries(queryParameters) to create the query string. Determine the symbol to be either ? or & based on the length of queryString and concatenate val to queryString only if it’s a string. Return the queryString or an empty string when the queryParameters are falsy.

const objectToQueryString = (queryParameters: AnyObject) => {
  return queryParameters
    ? Object.entries(queryParameters).reduce(
        (queryString, [key, val], index) => {
          const symbol = queryString.length === 0 ? "?" : "&";
          queryString += val ? `${symbol}${key}=${val}` : "";
          return queryString;
        },
        ""
      )
    : "";
};

objectToQueryString({ page: "1", size: "2kg", key: undefined }); // '?page=1&size=2kg'