var twurl;
function shorturl(url) {
  var id = 'jisedaisystem';
  var key = 'R_c2f4a2e3934ffae72017f46dfe2c4d08';
  var api = 'http://api.bit.ly/shorten?version=2.0.1&format=json&callback=TwCallback&login=' + id + '&apiKey=' + key + '&longUrl=' + url;
  var script = document.createElement('script');
  script.type = 'text/javascript';
  script.src = api;
  document.body.appendChild(script);
  twurl = url;
}

function TwCallback(json) {
  $("#itemtwitter").html("<p><a target=\"_blank\" href=\"http://twitter.com/home?status=【GMOとくとくショップ】" + json.results[twurl]['shortUrl'] + "\"><img src=\"/common/img/btn_twitter_01.gif\" onmouseover=\"this.src='/common/img/btn_twitter_01_over.gif'\" onmouseout=\"this.src='/common/img/btn_twitter_01.gif'\" /></a></p>");
}