Question

要求： 1）在多个段（比如大小 - 1 GB / 500 MB）中创建拆分拉链文件，以便可以通过浏览器下载。所有段的总拉链量可能超过10 GB 2）zip内容可以是多个文件或包含子文件夹和文件的文件夹 3）以流的形式从云中读取文件的内容。文件的元信息（如文件夹层次结构）是本地可用的

我正在使用DotNetZip库来完成任务。代码如下：

long length = default(long);
            Stream fileReadStream;

            long Space = default(long);
            string tempZipFile = string.Empty;
            FileZipStatus oldStatue = new FileZipStatus();
            byte[] Buffer = new byte[1024 * 1024];

            if (zipFileName != null && !zipFileName.ToUpper().EndsWith(".ZIP")) zipFileName += ".zip";
            string strTempFolder = "";
            using (Ionic.Zip.ZipFile zip = new Ionic.Zip.ZipFile())
            {
                try
                {
                    strTempFolderPath = tempZipOutPutFilePath + "\\";
                    string strTempFolderName = DateTime.Now.Ticks.ToString();
                    strTempFolder = strTempFolderPath + strTempFolderName;
                    if (userFileList.Count > 0)
                    {
                        if (Directory.Exists(strTempFolder))
                        {
                            Directory.Delete(strTempFolder);
                        }
                        Directory.CreateDirectory(strTempFolder);
                    }
                    foreach (UserFile userFile in userFileList)
                    {
                        WebResponse response = null;
                        try
                        {
                            WebRequest request = null;
                            IDictionary<string, object> _dictionary = new Dictionary<string, object>();
                            /// First 
                            FileSystemEnum fileSysEnum = FileSystemBase.GetFileSystemEnumByStorageId(userFile.StorageId);
                            IFileSystemLib ifileSystemLocal = FileSystemFactory.GetSpecificInstance(fileSysEnum);

                            fileReadStream = ifileSystemLocal.GetFile(userFile.FilePath, userFile.GuidName, ref request, ref response, _dictionary);
                            long filesize = default(long);

                            long.TryParse(ifileSystemLocal.GetFileContentLength(userFile.FilePath, userFile.GuidName).ToString(), out filesize);
                            Space = (Space > default(long)) ? (Space + filesize) : filesize;
                            //Now we have to store the data, so that we must access the file

                            int dataToRead;
                            FileStream writeStream = new FileStream(strTempFolder + "\\" + userFile.FileName, FileMode.Create, FileAccess.Write);
                            while ((dataToRead = fileReadStream.Read(Buffer, 0, Buffer.Length)) > 0)
                            {
                                writeStream.Write(Buffer, 0, dataToRead);
                            }
                            writeStream.Close();

                            zip.AddFile(strTempFolder + "\\" + userFile.FileName, userFile.RelativePath);
                            fileReadStream.Close();                            
                        }
                        catch (Exception ex)
                        {
                            LogManager.Trace(ex, "ZIpping Block - ZIPFileName", zipFileName + "File to zip" + userFile.GuidName);
                        }
                        finally
                        {
                            if (response != null) response.Close();
                        }
                    }
                }
                catch (Exception ex)
                {
                    _currentStatus = FileZipStatus.NotAvailable;
                    oldStatue = UpdateZipStatus(ObjectZipID, Space, FileZipStatus.Failed);
                    throw ex;
                }
                finally
                {   
                }
                try
                {
                    zip.Comment = "This zip was created at " + System.DateTime.Now.ToString("G");
                    zip.MaxOutputSegmentSize = 200 * 1024 * 1024;   // 200 mb
                    zip.Save(strTempFolderPath + "\\" + zipFileName);
                    oldStatue = UpdateZipStatus(ObjectZipID, Space, FileZipStatus.Available);
                    length = new FileInfo(strTempFolderPath + "\\" + zipFileName).Length;
                    _currentStatus = FileZipStatus.Available;
                    // deleting temp folder
                    Directory.Delete(strTempFolder, true);
                }
                catch (Exception ex)
                {
                    _currentStatus = FileZipStatus.NotAvailable;
                    oldStatue = UpdateZipStatus(ObjectZipID, Space, FileZipStatus.Failed);
                    length = default(long);
                    throw ex;
                }
            }

上述代码中使用了DotNetZip libray 的限制。它要么需要 a）保存在磁盘上的文件作为输入。在那种情况下，可以为每个文件传递文件夹层次结构信息。要么 2）如果将流作为输入传递，则无法为文件传递文件夹层次结构信息。

我需要传递每个文件的文件夹层次结构信息，以及从流中读取输入。由于zip内容可能很大（可能超过10 GB），不希望将文件保存在Web服务器的临时存储中。任何人都可以帮助您在创建zip文件时如何传递文件夹层次结构？感谢

Answer 1

我得到了解决方案。这是代码

private void button2_Click(object sender, EventArgs e)
        {
            using (SqlConnection sqlConn = new SqlConnection(@"Data Source=BBATRIDIP\SQLSERVER2008R2;Initial Catalog=test;Integrated Security=True"))
            {
                string query = String.Format(@"SELECT [FilePath],[FileName],[FileData] FROM [TestTable]");
                SqlCommand cmd = new SqlCommand(query, sqlConn);
                cmd.Connection.Open();

                System.IO.MemoryStream memStream = null;
                ZipFile zip = new ZipFile();
                zip.MaxOutputSegmentSize = 1024 * 1024; // 1MB each segment size would be
                // the above line would split zip file into multiple files and each file
                //size would be 1MB
                using (SqlDataReader reader = cmd.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        byte[] data = (byte[])reader["FileData"];
                        memStream = new System.IO.MemoryStream(data);
                        string strFile = reader["FilePath"].ToString() + "\\" + reader["FileName"].ToString();
                        ZipEntry ze = zip.AddEntry(strFile, memStream);
                    }
                }
                zip.Save(@"e:\MyCustomZip.zip");
                memStream.Dispose();
                MessageBox.Show("Job Done");
                // here u can save the zip in memory stream also there is a overload insteaa of saving in HD
            }
        }

Answer 2

此方法将zip内容存储在内存中。因此，当zip内容很大时，比如说超过5 GB然后就会崩溃。需要写入映射到物理文件的fileOutputStream

如何使用DotNetZip库从内存流创建zip文件时传递文件夹层次结构

2 个答案: