asp.net文件下载demo与相关问题的处理

下载的demo（可显示文件的总大小，并解决了下载完成自动结束下载）

 //分块下载
        private void downLoadPackage()
        {
            System.Web.HttpServerUtility server = System.Web.HttpContext.Current.Server;
            string fileName = "aaa.apk";
            //路径
            string filePath = server.MapPath("DownLoadPackage/aaa.apk")；

            if (!File.Exists(filePath)) return;
            
            FileInfo info = new FileInfo(filePath);
            //指定块大小   
            long chunkSize = 4096;
            //建立一个4K的缓冲区   
            byte[] buffer = new byte[chunkSize];
            //剩余的字节数   
            long dataToRead = 0;
            FileStream stream = null;
            try
            {
                //打开文件   
                stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read);
                
                dataToRead = stream.Length;

                //添加Http头   
                HttpContext.Current.Response.ContentType = "application/octet-stream";
                HttpContext.Current.Response.AddHeader("Content-Disposition", "attachement;filename=" + HttpUtility.UrlEncode(fileName));
                HttpContext.Current.Response.AddHeader("Content-Length", dataToRead.ToString());

                while (dataToRead > 0)
                {
                    if (HttpContext.Current.Response.IsClientConnected)
                    {
                        int length = stream.Read(buffer, 0, Convert.ToInt32(chunkSize));
                        HttpContext.Current.Response.OutputStream.Write(buffer, 0, length);
                        HttpContext.Current.Response.Flush();
                        HttpContext.Current.Response.Clear();
                        dataToRead -= length;
                    }
                    else
                    {
                        //防止client失去连接   
                        dataToRead = -1;
                    }
                }
            }
            catch (Exception ex)
            {
                HttpContext.Current.Response.Write("Error:" + ex.Message);
            }
            finally
            {
                if (stream != null)
                {
                    stream.Close();
                }
                HttpContext.Current.Response.Close();
            }
        }

iis上无法下载.apk和.ipa的问题

单击“新建”，建立新的MIME类型；

扩展名是：.apk MIMI类型是：application/vnd.android.package-archive

扩展名是：.ipa MIMI类型是：application/iphone