zipping & unzipping files in C#

Question

Friends I need to zip & unzip files programmatically in C#. Are there any classes in .NET framework to do this(Like java.util.zip.* in Java)? Any suggestions on how to proceed?

Administrator · Answer

Hi I don't know about .NET specifically but this is a port of a VB call to zlib (you can get the zlib library itself from loads of places) using System; using System.IO; using System.Runtime.InteropServices; namespace Compression { /// /// Provides interfaces to Compress/Decompress strings byte arrays /// public class StringCompression { public StringCompression() { // // TODO: Add constructor logic here // } // // Do not need it for just ten byes !!!! // [DllImport(\develop\CompTest\lib\zlib.dllSetLastError=true)] private static extern int compress2( [MarshalAs(UnmanagedType.LPArray)] byte[] dest ref int destLen [MarshalAs(UnmanagedType.LPArray)] byte[] src int srcLen int level ); [DllImport(\develop\CompTest\lib\zlib.dllSetLastError=true)] private static extern int uncompress( [MarshalAs(UnmanagedType.LPArray)] byte[] dest ref int destLen [MarshalAs(UnmanagedType.LPArray)] byte[] src int srcLen ); /// /// C# Implementation of VB ReDim function /// /// /// /// private static byte[] ReDim( byte[] aData long lLength ) { byte[] aRetVal = new byte[lLength]; for ( long l = 0; l < aData.Length && l < lLength ; l++ ) { aRetVal[l] = aData[l]; } return aRetVal; } public static String DecompressString2ByteArray(byte[] aData) { // // Indexing is a bit different in c# than it is in VB that is why // we have to add +1 here and there ... // if (aData.Length < 10) return ; string res; res = ; try { System.Text.ASCIIEncoding objAsc = new System.Text.ASCIIEncoding(); // // For ten byte memory move it is not worth // importing and calling another .dll just do it ! // byte[] aSize = new byte[9+1]; long pos = aData.Length - (9 + 1); for (int i =0; i < 10; i ++) { aSize[i] = aData[pos+i]; } int lSize; lSize = int.Parse (objAsc.GetString(aSize)); byte[] aBuffer = new byte [lSize]; uncompress ( aBuffer ref lSizeaData aData.Length -(9+1) ); res = objAsc.GetString(aBuffer); } catch (System.ExecutionEngineException eex ) { String s = eex.StackTrace; res = ; } catch ( Exception ex ) { String s = ex.StackTrace; res = ; } finally { } return res; } public static byte[] CompressString2ByteArray(String inpstr) { System.Text.ASCIIEncoding objAsc = new System.Text.ASCIIEncoding(); byte[] aData = objAsc.GetBytes(inpstr); byte[] aCompData = new byte[0]; int lLenght lBufferSize; lLenght = inpstr.Length; lBufferSize = inpstr.Length; //FileLog( BufferSize before:  + lBufferSize.ToString() ); lBufferSize = lBufferSize + (int)(lBufferSize * 0.01) + 12; //FileLog( BufferSize after:  + lBufferSize.ToString() ); // // Indexing is a bit different in c# than it is in VB that is why // we have to add +1 here and there ... // try { aCompData = new byte[lBufferSize]; compress2 ( aCompData ref lBufferSizeaData lLenght 9 ); string len; len = lLenght.ToString().PadLeft (10'0'); aCompData = ReDim( aCompData lBufferSize + (9 + 1)); byte[] aLenght = objAsc.GetBytes(len); // // For ten byte memory move it is not worth // importing and calling another .dll just do it ! // long pos = aCompData.Length - (9 + 1); for (int i =0; i < 10; i ++) { aCompData[pos+i] = aLenght [i]; } } catch (System.ExecutionEngineException eex ) { String s = eex.StackTrace; aCompData = null; } catch ( Exception ex ) { String s = ex.StackTrace; aCompData = null; } finally { } //FileLog(Compression result :  + objAsc.GetString( aCompData ) ); return aCompData; } } }