jQuery jsPdf 导出pdf

1、头部引入js

<script src="/static/js/main/jquery-3.3.1.min.js"></script>
<script src="/static/js/dist/html2canvas.min.js"></script>
<script src="/static/js/dist/jsPdf.debug.js"></script>

2、代码实现

function exportPdf() {
    html2canvas(document.getElementById("exportContent"), {
        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 / 595.28 * 841.89;
            //未生成pdf的html页面高度
            var leftHeight = contentHeight;
            //pdf页面偏移
            var position = 0;
            //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 = 555.28;
            var imgHeight = 555.28/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', 20, 0, imgWidth, imgHeight );
            } else {
                while(leftHeight > 0) {
                    pdf.addImage(pageData, 'JPEG', 20, position, imgWidth, imgHeight)
                    leftHeight -= pageHeight;
                    position -= 841.89;
                    //避免添加空白页
                    if(leftHeight > 0) {
                        pdf.addPage();
                    }
                }
            }

            pdf.save('xxxx.pdf');
        }
    })
}