简单JSONP请求器

jsonp.js

function jsonp(url, f) {
  return new Promise((resolve, reject) => {
    f = f || 'callback';
    const n = `_jsonpCb` + Date.now() + parseInt(Math.random() * 100000, 10);
    window[n] = (data) => {
      resolve(data);
      document.body.removeChild(s);
    };
    const s = document.createElement('script');
    s.onerror = (e) => reject(e);
    s.type = 'text/javascript';
    s.src = url + (url.indexOf('?') === -1 ? '?' : '&') + `${ f }=${ n }`;
    document.body.appendChild(s);
  });
}

// 测试
jsonp('https://www.reddit.com/r/aww.json', 'jsonp')
  .then(d => console.log('ok', d))
  .catch(e => console.error('error', e));

帅