html通过canvas转成base64的方法

<!--生成后存放的IMG-->
<img src="" id="saveImages" alt="">

<a href="javascript:;" class="create">生成海报</a>

<!--用来生成的HTML-->
<div id="saveContent" class="saveContent">
    <img src="">
    <div class="name pa"></div>
    <div class="msg pa"></div>
</div>
<style>
#saveContent{width: 7.5rem; height: 12.27rem; position: relative;}
#saveContent img{ width: 100%;}
#saveContent .name{color: #7c5234;font-size: .3rem;top: 6.55rem;line-height: .6rem;text-align: center;left: 0;right: 0;}
#saveContent .msg{color: #7c5234;font-size: .24rem;top: 7.35rem;text-align: center;left: 0;right: 0;}
#saveContent .msg span{ color: #cf5350; font-size: .36rem;}
</style>

<!--使用最新版本的html2canvas-->
<!--官网https://html2canvas.hertzen.com/-->
<script src="//html2canvas.hertzen.com/dist/html2canvas.min.js"></script>
<script src="//static.leiting.com/lib/jquery-1.9.0.min.js"></script>
<script>
//生成
$(function(){
    var isCreate=false;
    $('a.create').on('click',function(){
        isCreate=true;
        
        $('#saveContent img').attr('src','//activity.leiting.com/wd/201904/data/images/pop/1.jpg');
        $('#saveContent .name').html('aaaaaa');
        $('#saveContent .msg').html('bbbbbbbbbb');
        html2canvas(document.getElementById('saveContent'), {
            onrendered: function(ca) {
                $('#saveImages').attr('src',ca.toDataURL('image/jpeg'));
            }
        });
    })
})
</script>