1.设定一个要生成海报的元素

<div id="viewBox" res="box">内容....</div>

2.引进js

Poster:function(){
    var that = this;
    var DomeW=that.$refs.box.offsetWidth;//获取目标元素的宽高
    var DemoH = that.$refs.box.offsetHeight;//获取目标元素的宽高
    html2canvas(document.querySelector("#viewBox"),{useCORS:true,width:DomeW,height:DemoH}).then(function(canvas) {
    var imgUri = canvas.toDataURL("image/png").replace("image/png", "image/octet-stream"); // 获取生成的图片的url
     console.log(imgUri )；//生成图片base64
    })
},