ASP.NET下载网络图片

        /// <summary>
        /// 获取网页中的图片路径list集合
        /// </summary>
        /// <param name="webUrl"></param>
        /// <returns></returns>
        public static List<string> GetPicUrl(string webUrl) {
            HttpClient http = new HttpClient();
            Task<string> task = http.GetStringAsync(webUrl);
            List<string> list = new List<string>();
            Regex reg = new Regex("src=\"[^\"]*[(.jpg)(.png)(.gif)(.bmp)(.ico)]\"");
            //Regex reg = new Regex("src=\"[^\"]*[(.mp3)]\"");
            MatchCollection mc = reg.Matches(task.Result);
            foreach (Match m in mc)
            {
                string src = m.Value;
                src = src.Replace("src=", "").Replace("\"", "");
                list.Add(src) ;
            }
            return list;
        }

        /// <summary>
        /// 下载网络图片
        /// </summary>
        /// <param name="PicSourceUrl">网络图片地址</param>
        /// <param name="filePath">保存本地地址</param>
        /// <returns></returns>
        public static bool DownPic(string PicSourceUrl, string filePath)
        {
            WebRequest request = WebRequest.Create(PicSourceUrl);
            WebResponse response = request.GetResponse();
            Stream reader = response.GetResponseStream();
            FileStream writer = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.Write);
            try
            {
                byte[] buff = new byte[1024];
                int c = 0; //实际读取的字节数
                while ((c = reader.Read(buff, 0, buff.Length)) > 0)
                {
                    writer.Write(buff, 0, c);
                }
                writer.Close();
                writer.Dispose();
                reader.Close();
                reader.Dispose();
                response.Close();
            }
            catch (Exception ex)
            {
                return false;
            }
            finally
            {
                if (writer != null)
                {
                    writer.Close();
                    writer.Dispose();
                }
                if (reader != null)
                {
                    reader.Close();
                    reader.Dispose();
                }
                if (response != null)
                {
                    response.Close();
                }
            }
            return true;
        }

        /// <summary>
        /// 保存网络文字result到url中
        /// </summary>
        /// <param name="webUrl">网络文字的http地址</param>
        /// <param name="url">网络文字需要保存的地址</param>
        public static void SaveTxt(string webUrl,string url) {
            HttpClient http = new HttpClient();
            Task<string> task = http.GetStringAsync(webUrl);
            string result = task.Result;
            File.WriteAllText(@url, result);
        }