想截取浏览器上内容，并做成图片保存到本地。
可以使用html2canvas.js进行操作。
<!DOCTYPE html><html lang="en"><head> ???<meta charset="UTF-8"> ???<title>Title</title> ???<script src="~/Jquery/jquery-1.10.2.js"></script> ???<script src="https://cdn.bootcss.com/html2canvas/0.5.0-beta4/html2canvas.js"></script></head><body> ???@*原始图片*@ ???<div class="my-div"> ???????<img style="width: 400px; height: 300px" src="~/Img/longmao.jpg" /> ???</div> ???<br /> ???<input type="button" onclick="set()" value="截图" /> ???@*截取后存放图片的位置*@ ???<img id="img" /> ???<script> ???????function set() { ???????????//要转换为图片的dom对象 ???????????var element = document.querySelector(‘.my-div‘); ???????????//要显示图片的img标签 ???????????var image = document.querySelector(‘#img‘); ???????????//调用html2image方法 ???????????html2image(element, image); ???????????function html2image(element, image) { ???????????????html2canvas(element).then(function (canvas) { ???????????????????var imageData = canvas.toDataURL(1); ???????????????????//此时图片已经可以显示了 ???????????????????image.src = imageData; ???????????????}); ???????????} ???????} ???</script></body></html>把数据传入后台，将图片保存到本地。传输后台的数据是Base64的数据，需要转换
???????public string Set(string imgdata) ???????{ ???????????try ???????????{ ???????????????var strbase64 = imgdata; ???????????????string dummyData = strbase64.Trim().Replace("data:image/png;base64,", "").Replace("%", "").Replace(",", "").Replace(" ", "+"); ???????????????if (dummyData.Length % 4 > 0) ???????????????{ ???????????????????dummyData = dummyData.PadRight(dummyData.Length + 4 - dummyData.Length % 4, ‘=‘); ???????????????} ???????????????byte[] arr = Convert.FromBase64String(dummyData); ???????????????MemoryStream ms = new MemoryStream(arr); ???????????????Bitmap bmp = new Bitmap(ms); ???????????????var imagePath = AppDomain.CurrentDomain.BaseDirectory + "123.png"; ???????????????bmp.Save(imagePath, System.Drawing.Imaging.ImageFormat.Png); ???????????????ms.Close(); ???????????} ???????????catch (Exception ex) ???????????{ ???????????????Console.WriteLine(ex); ???????????????return TAjaxCallBack.ERROR; ???????????} ???????}JS截取页面，并保存到本地
原文地址：https://www.cnblogs.com/xiaoyaodijun/p/9268929.html