<div id="code"></div><img id="img"/><script type="text/javascript">  var qrcode=$("#code").qrcode({    render:'canvas||table',    width: 200, //寬度    height:200, //高度    text: "http://www.baidu.com" //任意內容  }).hide();  var canvas=qrcode.find('canvas').get(0);  //如果有循環,此句必不可少 qrcode.find('canvas').remove();  var data = canvas.toDataURL('image/jpg');  $('#img').attr('src',data) ;  saveFile(data,"fd范德薩范德薩");  //轉為圖片的方法,需要上門的data  function saveFile(data,filename){    var save_link=document.createElementNS('http://www.w3.org/1999/xhtml', 'a');    save_link.href=data;    save_link.download=filename;    var event=document.createEvent('MouseEvents');    event.initMouseEvent('click',true,false,window,0,0,0,0,0,false,false,false,false,0,null);    save_link.dispatchEvent(event);  };</script>