将页面导出pdf
在课堂评测系统v3版本中有用到,代码如下
/**
* 导出PDF
* @ dom 导入pdf 内容
*/
toPDF: function (dom) {
let pdfContentHeight = dom.offsetHeight;
let pdfContentWith = dom.offsetWith;
let copyDom = $("<div/>");
copyDom.addClass('super');
copyDom.width(pdfContentWith + "px");
copyDom.height(pdfContentHeight + "px");
$('body').append(copyDom);
html2canvas(dom, {
allowTaint: true,
height: pdfContentHeight,//给canvas设置高度,
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;
//页面偏移
var position = 50;
//a4纸的尺寸[595.28,841.89],html页面生成的canvas在pdf中图片的宽高
var imgWidth = 500;
var imgHeight = 500 / 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', 40, 0, imgWidth, imgHeight);
} else {
while (leftHeight > 0) {
pdf.addImage(pageData, 'JPEG', 40, position, imgWidth, imgHeight)
leftHeight -= pageHeight;
position -= 841.89;
//避免添加空白页
if (leftHeight > 0) {
pdf.addPage();
}
}
}
pdf.save('report_pdf_' + new Date().getTime() + '.pdf');
//移除dom中添加的元素
$('.super').remove();
},
background: "#fff"
});
},
stuMonthTablePDF: function () {
let pdfDom = document.querySelector('.pdfContent');
this.toPDF(pdfDom);
},