// 参数
const shareInfo = {
  text: {
    content: str
  },
  attachments: [
   {
     msgtype: "video"
     {
      video: {
        mediaid: "3-jsbVyb-e-bksMCC-659ykEbS9JaomHPUD_D7R6k6tVSuISM7zC3707HTbh_SD0G"
      }
     }
   }
  ]
}
wx.qy.shareToExternalMoments(shareInfo, function(e) {
  console.log(e);
});