code: function parseResponse(body) {
    var pgt = '';
    var result = body.match(/action="([\s\S]*?)"/);
    if (result) {
      result = result[1];
  
      var uri = url.parse(result, true);
      var pathname = uri.pathname;
  
      pgt = pathname.substr(pathname.lastIndexOf('/') + 1);
    }
  
    return pgt;
  }
docs: 解析出pgt
  @param body
  @return {String} pgtId