C#代码实现URL下载文件至本地

 public static void GetFileFromNetUrl(string url,string houzhui,string name,string wenjian)//下载
        {
            /// <summary>
            /// 下载文件
            /// </summary>
            /// <param name="url">url路径,如:http://1.1.1.1/1.txt</param>
            /// <param name="saveFullPath">保存文件全路径,如 G:\1.txt</param>
            /// <param name="houzhui">文件后缀如.doc .pdf</param>
            /// <param name="name">文件名称</param>
            /// <param name="wenjian">文件夹名称</param>
            /// <returns></returns>
                string saveFullPath = "D://"+ wenjian + "//"+name+houzhui;
                WebRequest webRequest = null;
                WebResponse webResponse = null;
                Stream stream = null;
                FileStream fileStream = null;
                try
                {
                    webRequest = WebRequest.Create(url);

                    //webRequest.Credentials = CredentialCache.DefaultCredentials;
                    //webRequest.UseDefaultCredentials = true;

                    webResponse = webRequest.GetResponse();
                    stream = webResponse.GetResponseStream();
                    if (stream == null)
                    {
                        throw new Exception("当前流为空!");
                    }
                    fileStream = System.IO.File.Create(saveFullPath);