js导出div为图片

<div id="tbl_exception">            <p style=" color: chartreuse;">你的名字<span style='color:aqua; text-shadow:0 0 2px blue;'>aaa</span></p>        </div>        <a id="Down">            <img id="img" />        </a>        <button id="btn_screen">点击</button>

<script type="text/javascript" src="js/html2canvas.js"></script>$("#btn_screen").on("click", function() {                html2canvas($("#tbl_exception"), {                    height: $("#tbl_exception").outerHeight() + 20,                    onrendered: function(canvas) {                        var url = canvas.toDataURL();                        $("#img").attr("src", url);                        $("#Down").attr("href", url);                    }                });            });

html2canvas

图片下载：a标签的download属性