dmdb/ImportExport.cs

98 lines
3.8 KiB
C#

using System;
using System.IO;
using ICSharpCode.SharpZipLib.Zip;
namespace dezentrale
{
public class ImportExport
{
public static bool ZipExport(string outFile, string password = null)
{
if (!Directory.Exists(Program.config.MemberDirectory))
{
Console.WriteLine($"Cannot find directory '{Program.config.MemberDirectory}'");
return false;
}
try
{
// Depending on the directory this could be very large and would require more attention
// in a commercial package.
string[] filenames = Directory.GetFiles(Program.config.MemberDirectory, "member-*.xml");
if (File.Exists(outFile))
{
string backupName = $"{outFile}.bak";
if (File.Exists(backupName)) File.Delete(backupName);
File.Move(outFile, backupName);
}
// 'using' statements guarantee the stream is closed properly which is a big source
// of problems otherwise. Its exception safe as well which is great.
using (ZipOutputStream s = new ZipOutputStream(File.Create(outFile)))
{
/*#if DEBUG
s.SetLevel(0); // 0 - store only to 9 - means best compression
#else*/
s.SetLevel(9); // 0 - store only to 9 - means best compression
//#endif
s.Password = password; //null is a desired value for "no encryption"
byte[] buffer = new byte[4096];
foreach (string file in filenames)
{
// Using GetFileName makes the result compatible with XP
// as the resulting path is not absolute.
var entry = new ZipEntry(Path.GetFileName(file));
// Setup the entry data as required.
// Crc and size are handled by the library for seakable streams
// so no need to do them here.
// Could also use the last write time or similar for the file.
entry.DateTime = DateTime.Now;
s.PutNextEntry(entry);
using (FileStream fs = File.OpenRead(file))
{
// Using a fixed size buffer here makes no noticeable difference for output
// but keeps a lid on memory usage.
int sourceBytes;
do
{
sourceBytes = fs.Read(buffer, 0, buffer.Length);
s.Write(buffer, 0, sourceBytes);
} while (sourceBytes > 0);
}
}
// Finish/Close arent needed strictly as the using statement does this automatically
// Finish is important to ensure trailing information for a Zip file is appended. Without this
// the created file would be invalid.
s.Finish();
// Close is important to wrap things up and unlock the file.
s.Close();
}
}
catch (Exception ex)
{
Console.WriteLine($"Exception during processing {ex.Message}");
// No need to rethrow the exception as for our purposes its handled.
return false;
}
return true;
}
public static bool ZipImport(string inFile, string password = null)
{
return false;
}
}
}