使用HttpWebRequest下载网页图片并保存至本地

using System;
using System.Net;
using System.IO;
using System.Text;

namespace mynamespace
{
    public class Downloader
    {
        /// <summary>
        /// 下载图片
        /// </summary>
        /// <param name="picUrl">图片Http地址</param>
        /// <param name="savePath">保存路径</param>
        /// <param name="timeOut">Request最大请求时间，如果为-1则无限制</param>
        /// <returns></returns>
        public static bool DownloadPicture(string picUrl, string savePath,int timeOut)
        {
            bool value = false;
            WebResponse response = null;
            Stream stream = null;
            try
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(picUrl);
                if (timeOut != -1) request.Timeout = timeOut;
                response = request.GetResponse();
                stream = response.GetResponseStream();
                if (!response.ContentType.ToLower().StartsWith("text/"))
                    value = SaveBinaryFile(response, savePath);
            }