潍坊百度网站优化,wordpress博客dux主题,网建设门户网站,网站 快照 更新慢数据量太大使用dom》canvas》image》pdf.addimage方法弊端是canvas超出
浏览器承受像素会图片损害#xff0c;只能将其切割转成小块的canvas,每一次调用html2canvas等待时间都很长累积时间更长#xff0c;虽然最终可以做到抽取最小dom节点转canvas拼接数据#xff0c;但是死…数据量太大使用dom》canvas》image》pdf.addimage方法弊端是canvas超出
浏览器承受像素会图片损害只能将其切割转成小块的canvas,每一次调用html2canvas等待时间都很长累积时间更长虽然最终可以做到抽取最小dom节点转canvas拼接数据但是死卡
jspdf提供了不需要操作dom的方法 Global - Documentation 使用line方法和text方法可以通过传递线坐标和文字位置在pdf页上画线和文字组成表格
function getStrLen(cItem, strLen) {let str typeof cItem string || typeof cItem number ? cItem : nulllet len Math.ceil(str.length / strLen)if (len 1) {return str}str String(str)let strn for (let i 0; i len; i) {strn strn str.substring(i * strLen, (i 1) * strLen) \n}return strn
}async function downPDF(list, columns) {// 1in 2.54cm 25.4 mm 72pt 6pclet tablePdf null
//绘制表格的参数let cardTop 10, cardLeft 7, textLeft 9, textTop 14, oneColumnNum 35, oneRowNum 7, oneCellWidth 28, oneCellHeight 8, oneStrLen 5, pdfWidth 203, pdfHeight 290, strLen 8let endPageNum 0
//表格数据的整理
//整理格式成一个二维数组第一层以列为单个元素元素是整列的值组成的数组let testList columns[0].childrenlet propList testList.map((item) {return { prop: item.props.prop, label: item.props.label }})let dataList []propList.forEach((item, index) {let cArr []cArr.push(item.label)list.forEach((cItem, cIndex) {cArr.push(cItem[item.prop])})dataList.push(cArr)})console.log(dataList)//处理好表格数据的二维数组配置pdf对象tablePdf new jsPDF(p, mm, a4);
//解决中文乱码tablePdf.addFont(/fonts/SourceHanSansCN-Normal.ttf, SourceHanSans, normal)tablePdf.setFont(SourceHanSans);//1doc中设置font: SourceHanSans // 2style中设置tablePdf.setLineWidth(0.1)tablePdf.setFontSize(8)tablePdf.line(cardLeft, cardTop, pdfWidth, cardTop);let columnPages Math.ceil(dataList.length / oneRowNum) 1let rowPages Math.ceil(dataList[0].length / oneColumnNum) 1let currentData []for (let i 1; i columnPages; i) {
//横向分页let currentColumnData dataList.slice((i - 1) * oneRowNum, i * oneRowNum)
//纵向分页for (let rowInddex 1; rowInddex rowPages; rowInddex) {currentData currentColumnData.map((item, index) {return item.slice((rowInddex - 1) * oneColumnNum, rowInddex * oneColumnNum)})currentData.forEach((item, index) {item.forEach((cItem, cIndex) {cItem getStrLen(cItem, strLen)//填文字超过长度换行tablePdf.text(cItem, textLeft index * oneCellWidth, textTop cIndex * oneCellHeight, left)//画一次横线if (index currentData.length - 1) {tablePdf.line(cardLeft, cardTop cIndex * oneCellHeight, pdfWidth, cardTop cIndex * oneCellHeight);//画最后一条横线if (cIndex item.length - 1) {tablePdf.line(cardLeft, cardTop (cIndex 1) * oneCellHeight, pdfWidth, cardTop (cIndex 1) * oneCellHeight);endPageNum item.lengthlet ks (pdfHeight - cardTop) / oneColumnNumfor (let l 0; l oneRowNum 1; l) {tablePdf.line(cardLeft l * oneCellWidth, cardTop, cardLeft l * oneCellWidth, endPageNum * ks cardTop);}}}})});if (rowInddex 1 ! rowPages) {tablePdf.addPage();}}if (i 1 ! columnPages) {tablePdf.addPage();}}tablePdf.save(dd.pdf)
}数组datalist结构
效果
