JS把链接生成二维码图片方法分析

<p id="code"></p>
<img id="img"/>
<script type="text/javascript">
 var qrcode=$("#code").qrcode({
 render:'canvas||table',
 width: 200, //宽度
 height:200, //高度
 text: "http://www.baidu.com" //任意内容
 }).hide();
 var canvas=qrcode.find('canvas').get(0);
 //如果有循环,此句必不可少 qrcode.find('canvas').remove();
 var data = canvas.toDataURL('image/jpg');
 $('#img').attr('src',data) ;
 saveFile(data,"fd范德萨范德萨");
 //转为图片的方法,需要上门的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>