protected void Button1_Click(object sender, EventArgs e) {
???????????string url = Server.MapPath("/img/image.png");
???????????FileInfo file = new FileInfo(url);
???????????Response.ContentType = "image/png";
???????????Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode("优惠券.png", System.Text.Encoding.UTF8));
???????????Response.WriteFile(url);
???????????Response.Flush();
???????}
保存网页上的图片到本地
原文地址：https://www.cnblogs.com/ZkbFighting/p/8603646.html