jj: Database version 0.0.3

Filesystem/Compression.vb

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+Imports System.IO
+Imports System.IO.Compression
+
+Friend Class Compression
+    Public Async Function CompressAsync(data As Byte()) As Task(Of Byte())
+        Return Await Task.Run(Function() As Byte()
+                                  Return Compress(data)
+                              End Function)
+    End Function
+
+    Public Function Compress(data As Byte()) As Byte()
+        ' ByteArray in Stream umwandeln
+        Using originalStream As New MemoryStream(data)
+            ' Ziel Stream erstellen
+            Using compressedStream As New MemoryStream()
+                ' Gzip-Stream erstellen, der alle Daten komprimiert und zu compressedStream durchleitet
+                '
+                '  > MemoryStream      > GzipStream          > MemoryStream  
+                '  originalStream  --> compressionStream --> compressedFileStream
+                '
+                Using compressionStream As New GZipStream(compressedStream, CompressionMode.Compress)
+                    originalStream.CopyTo(compressionStream)
+                    compressionStream.Close()
+                    Return compressedStream.ToArray()
+                End Using
+            End Using
+        End Using
+    End Function
+
+    Public Async Function DecompressAsync(data As Byte()) As Task(Of Byte())
+        Return Await Task.Run(Function() As Byte()
+                                  Return Decompress(data)
+                              End Function)
+    End Function
+
+    Public Function Decompress(data As Byte()) As Byte()
+        ' ByteArray in Stream umwandeln
+        Using compressedStream As New MemoryStream(data)
+            ' Ziel Stream erstellen
+            Using decompressedStream As New MemoryStream()
+                ' Gzip-Stream erstellen, der alle Daten komprimiert und zu compressedStream durchleitet
+                '
+                '  > MemoryStream        > GzipStream            > MemoryStream  
+                '  compressedStream  --> decompressionStream --> decompressedStream
+                '
+                Using decompressionStream As New GZipStream(compressedStream, CompressionMode.Decompress)
+                    decompressionStream.CopyTo(decompressedStream)
+                    Return decompressedStream.ToArray()
+                End Using
+            End Using
+        End Using
+    End Function
+
+End Class