一.转pdf
// 导出页面为PDF格式
/* eslint-disable */
//不使用JQuery版的
import html2canvas from 'html2canvas'
import JsPDF from 'jspdf'/*** @param ele 要生成 pdf 的DOM元素(容器)* @param padfName PDF文件生成后的文件名字* */function downloadPDF(ele, pdfName) {let eleW = ele.offsetWidth// 获得该容器的宽let eleH = ele.offsetHeight// 获得该容器的高let eleOffsetTop = ele.offsetTop // 获得该容器到文档顶部的距离let eleOffsetLeft = ele.offsetLeft // 获得该容器到文档最左的距离var canvas = document.createElement('canvas')var abs = 0let win_in = document.documentElement.clientWidth || document.body.clientWidth // 获得当前可视窗口的宽度(不包含滚动条)let win_out = window.innerWidth // 获得当前窗口的宽度(包含滚动条)if (win_out > win_in) {// abs = (win_o - win_i)/2; // 获得滚动条长度的一半abs = (win_out - win_in) / 2 // 获得滚动条宽度的一半// console.log(a, '新abs');}canvas.width = eleW * 2 // 将画布宽&&高放大两倍canvas.height = eleH * 2var context = canvas.getContext('2d')context.scale(2, 2)context.translate(-eleOffsetLeft - abs, -eleOffsetTop)// 这里默认横向没有滚动条的情况,因为offset.left(),有无滚动条的时候存在差值,因此// translate的时候,要把这个差值去掉// html2canvas(element).then( (canvas)=>{ //报错// html2canvas(element[0]).then( (canvas)=>{html2canvas(ele, {dpi: 300,// allowTaint: true, //允许 canvas 污染, allowTaint参数要去掉,否则是无法通过toDataURL导出canvas数据的useCORS: true //允许canvas画布内 可以跨域请求外部链接图片, 允许跨域请求。}).then((canvas) => {var contentWidth = canvas.widthvar 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 = 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 = 595.28var imgHeight = 595.28 / contentWidth * contentHeightvar 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) {//在pdf.addImage(pageData, 'JPEG', 左,上,宽度,高度)设置在pdf中显示;pdf.addImage(pageData, 'JPEG', 80, 0, imgWidth, imgHeight)// pdf.addImage(pageData, 'JPEG', 20, 40, imgWidth, imgHeight);} else { // 分页while (leftHeight > 0) {pdf.addImage(pageData, 'JPEG', 0, position, imgWidth, imgHeight)leftHeight -= pageHeightposition -= 841.89//避免添加空白页if (leftHeight > 0) {pdf.addPage()}}}//可动态生成pdf.save(pdfName)})
}export default {downloadPDF
}
二.转img
import html2canvas from 'html2canvas'
/*** element 导出得元素* filename 文件名* ext 扩展文件名
*/export function exportImg(element, filename, ext){html2canvas(element, {useCORS: true}).then(canvas=>{if (navigator.msSaveBlob) {const blob = canvas.msToBlob() // IE10+return navigator.msSaveBlob(blob, name)} else {const imageurl = canvas.toDataURL('image/png')const aLink = document.createElement('a') // 创建a标签aLink.style.display = 'none'aLink.href = imageurlaLink.download = `${filename}.${ext}` // 下载文件名document.body.appendChild(aLink)aLink.click()document.body.removeChild(aLink) // 用完后移除元素}})
}