官网文档: http://html2canvas.hertzen.com/
使用的是 jquery 3.2.1 html2canvas 1.0.0-rc.7
截取根据id的指定区域:
var canvasOtherTopHeight = $(‘.heading‘).height() + 31 + $(‘#site-navbar‘).height(); // .heading是指定区域父级上面同级的dom,因为存在高度,所以要计算到内
function createCanvas(id, obj) { // 1.获取高度 let canvasObj = $(‘#‘ + id); // 2.区域为画布 // console.log(‘--==‘, canvasObj.width(), canvasObj.height(), canvasObj.offset().left, canvasObj.parent().parent().position().top); html2canvas(canvasObj.get(0), { useCORS: true, width: canvasObj.width() + 5, height: canvasObj.height() - excelHeight, x: canvasObj.offset().left, y: canvasObj.parent().top + canvasOtherTopHeight }).then(canvas => { // canvasObj.parent().find(‘.target-canvas-img‘).attr(‘src‘, canvas.toDataURL(‘image/png‘, 1.0)); canvasObj.parent().find(‘.canvas-wrapper .canvas-word‘).append(canvas); }); }
截取根据id的iframe的区域:
function createCanvas(id, obj) { // 1.获取高度 let canvasObj = $(‘#‘ + id); // 2.答案区域为图片 // console.log(‘--==‘, canvasObj.width(), canvasObj.height(), canvasObj.offset().left, canvasObj.parent().parent().position().top); // excel的高度 let excelHeight = canvasObj.find(‘.answer-con-excel-container iframe‘).height(); let iframeHtml = canvasObj.find(‘.answer-con-excel-container iframe‘); // 获取iframe内容 let iframeBody = iframeHtml.contents().find(‘body‘)[0]; html2canvas(iframeBody, { allowTaint: true, useCORS: true, width: 820, // TODO 截屏按照1920*1080分辨率下的预览窗口宽高 height: 800, x: 0, y: 0 }).then(canvas => { // canvasObj.parent().find(‘.target-canvas-img-excel‘).attr(‘src‘, canvas.toDataURL(‘image/png‘, 1.0)); canvasObj.parent().find(‘.canvas-wrapper .canvas-excel‘).append(canvas); }) }
其中参数 width height 可根据效果进行增减