js实现html转成pdf

svg2canvas: function(targetElem) {
 var svgElem = targetElem.find('svg');
 svgElem.each(function(index, node) {
 var parentNode = node.parentNode;
 //由于现在的IE不支持直接对svg标签node取内容，所以需要在当前标签外面套一层div，通过外层div的innerHTML属性来获取
 var tempNode = document.createElement('div');
 tempNode.appendChild(node);
 var svg = tempNode.innerHTML;
 var canvas = document.createElement('canvas');
 //转换
 canvg(canvas, svg);
 parentNode.appendChild(canvas);
 });
}

glyphicons2canvas: function(targetElem, fontClassName, fontFamilyName) {
 var iconElems = targetElem.find('.' + fontClassName);
 iconElems.each(function(index, inconNode) {
 var fontSize = $(inconNode).css("font-size");
 var iconColor = $(inconNode).css("color");
 var styleContent = $(inconNode).attr('style');
 //去掉"px"
 fontSize = fontSize.replace("px", "");
 var charCode = getCharCodeByGlyphiconsName(iconName);
 var myCanvas = document.createElement('canvas');
 //把canva宽高各增加2是为了显示图标完整
 myCanvas.width = parseInt(fontSize) + 2;
 myCanvas.height = parseInt(fontSize) + 2;
 myCanvas.style = styleContent;
 var ctx = myCanvas.getContext('2d');
 //设置绘图内容的颜色
 ctx.fillStyle = iconColor;
 //设置绘图的字体大小以及font-family的名字
 ctx.font = fontSize + 'px ' + fontFamilyName;
 ctx.fillText(String.fromCharCode(charCode), 1, parseInt(fontSize) + 1);
 $(inconNode).replaceWith(myCanvas);
 });
}
//根据glyphicons/glyphicon图标的类名获取到对应的char code
getCharCodeByGlyphiconsName: function(iconName) {
 switch (iconName) {
 case("glyphicons-resize-full"):
 return "0xE216";
 case ("glyphicons-chevron-left"):
 return "0xE225";
 default:
 return "";
 }
 }

html2canvas($("#myExportArea"), {
 onrendered: function(canvas) {
 var imgData = canvas.toDataURL('image/jpeg');
 var img = new Image();
 img.src = imgData;
 //根据图片的尺寸设置pdf的规格，要在图片加载成功时执行，之所以要*0.225是因为比例问题
 img.onload = function() {
 //此处需要注意，pdf横置和竖置两个属性，需要根据宽高的比例来调整，不然会出现显示不完全的问题
 if (this.width > this.height) {
 var doc = new jsPDF('l', 'mm', [this.width * 0.225, this.height * 0.225]);
 } else {
 var doc = new jsPDF('p', 'mm', [this.width * 0.225, this.height * 0.225]);
 }
 doc.addImage(imgData, 'jpeg', 0, 0, this.width * 0.225, this.height * 0.225);
 //根据下载保存成不同的文件名
 doc.save('report_pdf_' + new Date().getTime() + '.pdf');
 }
 },
 background: "#fff",
 //这里给生成的图片默认背景，不然的话，如果你的html根节点没设置背景的话，会用黑色填充。
 allowTaint: true //避免一些不识别的图片干扰，默认为false，遇到不识别的图片干扰则会停止处理html2canvas
});