引用网址：https://blog.csdn.net/weixin_30462049/article/details/99170485

/// <summary>
        /// 查看网络图片
        /// </summary>
        /// <param name="url"></param>
        private void LoadPic(string url)
        {
            System.Net.WebRequest webreq = System.Net.WebRequest.Create(textBox1.Text.Trim());
            webreq.Timeout = 20000;
            System.Net.WebResponse webres = webreq.GetResponse();
            using (System.IO.Stream stream = webres.GetResponseStream())
            {
                Image i = Image.FromStream(stream);
                i.Save("e:\\1.jpg");  //图片保存
                //pictureBox1.Image = i;  //图片显示
            }
        }