html2canvas实现截取指定区域或iframe的区域

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);
});}

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);
})
}