详解使用canvas保存网页为pdf文件支持跨域

<script type="text/javascript" src="js/html2canvas.js"></script><script type="text/javascript" src="js/html2canvas.min.js"></script><script type="text/javascript" src="js/jspdf.debug.js"></script>

 <div id="down_pdf">导出为PDF按钮</div> <div class="sta-main">需要获取为PDF的div</div>

<script type="text/javascript">/* var downPdf = document.getElementById("down_pdf"); */var downPdf = document.getElementById("down_pdf");$("#down_pdf").on("click", function() { var canvas2 = document.createElement("canvas"); let _canvas = document.querySelector('.sta-main'); //获取宽高 var w = parseInt(window.getComputedStyle(_canvas).width); var h = parseInt(window.getComputedStyle(_canvas) .height); //将canvas画布放大2倍，然后盛放在小的容器内，处理模糊 canvas2.width = w * 2; canvas2.height = h * 2; canvas2.style.width = w + "px"; canvas2.style.height = h + "px"; var context = canvas2.getContext("2d"); //处理偏移 context.scale(1.5, 1.5); //修改背景颜色，默认是黑色 $('.sta-main').css("background", "#fff") html2canvas( _canvas, { //处理pdf跨域获取不到跨域信息问题 taintTest : false, useCORS : true, allowTaint : false,  canvas : canvas2, dpi: 172,//导出pdf清晰度 onrendered: function (canvas) { var contentWidth = canvas.width; var contentHeight = canvas.height; //一页pdf显示html页面生成的canvas高度; var pageHeight = contentWidth / 592.28 * 841.89; //未生成pdf的html页面高度 var leftHeight = contentHeight; //pdf页面偏移 var position = 0; //html页面生成的canvas在pdf中图片的宽高（a4纸的尺寸[595.28,841.89]） var imgWidth = 595.28; var imgHeight = 592.28 / contentWidth * contentHeight; var pageData = canvas.toDataURL('image/jpeg', 1.0); var pdf = new jsPDF('', 'pt', 'a4'); //有两个高度需要区分，一个是html页面的实际高度，和生成pdf的页面高度(841.89) //当内容未超过pdf一页显示的范围，无需分页 if (leftHeight < pageHeight) { pdf.addImage(pageData, 'JPEG', 0, 0, imgWidth, imgHeight); } else { while (leftHeight > 0) { pdf.addImage(pageData, 'JPEG', 0, position, imgWidth, imgHeight) leftHeight -= pageHeight; position -= 841.89; //避免添加空白页 if (leftHeight > 0) { pdf.addPage(); } } } pdf.save('PDF的名字.pdf'); } }) $('.sta-main').css("background", "")})</script>