c# 通过地址下载流然后保存文件到本地

1.下载文件并保存文件到本地

        private void GetFileFromNetUrl(string url)

        {

            try

            {

                System.Net.WebRequest req = System.Net.WebRequest.Create(url);

                req.Method = "GET";

                //获得用户名密码的Base64编码  添加Authorization到HTTP头 不需要的账号密码的可以注释下面两行代码

                string code = Convert.ToBase64String(Encoding.ASCII.GetBytes(string.Format("{0}:{1}", "userName", "passWord")));

                req.Headers.Add("Authorization", "Basic " + code);

                byte[] fileBytes;

                using (WebResponse webRes = req.GetResponse())

                {

                    int length = (int)webRes.ContentLength;

                    HttpWebResponse response = webRes as HttpWebResponse;

                    Stream stream = response.GetResponseStream();

                    //读取到内存

                    MemoryStream stmMemory = new MemoryStream();

                    byte[] buffer = new byte[length];

                    int i;

                    //将字节逐个放入到Byte中

                    while ((i = stream.Read(buffer, 0, buffer.Length)) > 0)

                    {

                        stmMemory.Write(buffer, 0, i);

                    }

                    fileBytes = stmMemory.ToArray();//文件流Byte，需要文件流可直接return，不需要下面的保存代码

                    stmMemory.Close();

                    MemoryStream m = new MemoryStream(fileBytes);

                    string file = string.Format("F:\\666666666666.pdf");//可根据文件类型自定义后缀

                    FileStream fs = new FileStream(file, FileMode.OpenOrCreate);

                    m.WriteTo(fs);

                    m.Close();

                    fs.Close();

                }

            }

            catch (System.Exception ex)

            {

                throw ex;

            }

        }      

2.下载文件流，返回byte流

        private byte[] GetFileFromNetUrl(string url, string userName = "", string password = "")

        {

            try

            {

                System.Net.WebRequest req = System.Net.WebRequest.Create(url);

                req.Method = "GET";

                if (!string.IsNullOrEmpty(userName) && !string.IsNullOrEmpty(password))

                {

                    //获得用户名密码的Base64编码  添加Authorization到HTTP头

                    string code = Convert.ToBase64String(Encoding.ASCII.GetBytes(string.Format("{0}:{1}", userName, password)));

                    req.Headers.Add("Authorization", "Basic " + code);

                }

                byte[] fileBytes;

                using (WebResponse webRes = req.GetResponse())

                {

                    int length = (int)webRes.ContentLength;

                    HttpWebResponse response = webRes as HttpWebResponse;

                    Stream stream = response.GetResponseStream();

                    //读取到内存

                    MemoryStream stmMemory = new MemoryStream();

                    byte[] buffer = new byte[length];

                    int i;

                    //将字节逐个放入到Byte中

                    while ((i = stream.Read(buffer, 0, buffer.Length)) > 0)

                    {

                        stmMemory.Write(buffer, 0, i);

                    }

                    fileBytes = stmMemory.ToArray();//文件流Byte

                    stmMemory.Close();

                }

                return fileBytes;

            }

            catch (System.Exception ex)

            {

                throw ex;

            }

        }

c# 通过地址下载流然后保存文件到本地的相关教程结束。