Skip to main content

Compressing and DeCompressing a File in C#

Methods to compress file and decompress file using System.IO.Compression


Method to compress a file.

public void CompressFile ( string sourceFile, string destinationFile )

{

// Check File exists in the source path

if ( File.Exists ( sourceFile ) == false )

throw new FileNotFoundException ( );

// Create the streams and byte arrays

byte[] buffer = null;

FileStream sourceStream = null;

FileStream destinationStream = null;

GZipStream compressedStream = null;

try

{

// Read the bytes from the source file into a byte array

sourceStream =

new FileStream ( sourceFile, FileMode.Open, FileAccess.Read, FileShare.Read );

// Read the source stream values into the buffer

buffer =

new byte[sourceStream.Length];

int checkCounter = sourceStream.Read ( buffer, 0, buffer.Length );

if ( checkCounter != buffer.Length )

{

throw new ApplicationException ( );

}

// Open the FileStream to write

destinationStream =

new FileStream ( destinationFile, FileMode.OpenOrCreate, FileAccess.Write );

// Create a compression stream pointing to the destiantion stream

compressedStream =

new GZipStream ( destinationStream, CompressionMode.Compress, true );

// Now write the compressed data to the destination file

compressedStream.Write ( buffer, 0, buffer.Length );

}

catch ( ApplicationException ex )

{

MessageBox.Show ( ex.Message, "Error occured during compression", MessageBoxButtons.OK, MessageBoxIcon.Error );

}

finally

{

// Close all streams

if ( sourceStream != null )

sourceStream.Close ( );

if ( compressedStream != null )

compressedStream.Close ( );

if ( destinationStream != null )

destinationStream.Close ( );

}

}


Method to DeCompress a file.


public

void DecompressFile ( string sourceFile, string destinationFile )

{

// Check File exists in the source path

if ( File.Exists ( sourceFile ) == false )

throw new FileNotFoundException ( );

// Create the streams and byte arrays needed

FileStream sourceStream = null;

FileStream destinationStream = null;

GZipStream decompressedStream = null;

byte[] quartetBuffer = null;

try

{

// Read in the compressed source stream

sourceStream =

new FileStream ( sourceFile, FileMode.Open );

// Create a compression stream pointing to the destiantion stream

decompressedStream =

new GZipStream ( sourceStream, CompressionMode.Decompress, true );

// Read the footer to determine the length of the destiantion file

quartetBuffer =

new byte[4];

int position = (int)sourceStream.Length - 4;

sourceStream.Position = position;

sourceStream.Read ( quartetBuffer, 0, 4 );

sourceStream.Position = 0;

int checkLength = BitConverter.ToInt32 ( quartetBuffer, 0 );

byte[] buffer = new byte[checkLength + 100];

int offset = 0;

int total = 0;

// Read the compressed data into the buffer

while ( true )

{

int bytesRead = decompressedStream.Read ( buffer, offset, 100 );

if ( bytesRead == 0 )

break;

offset += bytesRead;

total += bytesRead;

}

// Now write to the destination file

destinationStream =

new FileStream ( destinationFile, FileMode.Create );

destinationStream.Write ( buffer, 0, total );

// Flush to clean out the buffer

destinationStream.Flush ( );

}

catch ( ApplicationException ex )

{

MessageBox.Show ( ex.Message, "An Error occured during compression", MessageBoxButtons.OK, MessageBoxIcon.Error );

}

finally

{

// Close all streams

if ( sourceStream != null )

sourceStream.Close ( );

if ( decompressedStream != null )

decompressedStream.Close ( );

if ( destinationStream != null )

destinationStream.Close ( );

}

}

Comments

Post a Comment

Popular posts from this blog

C# Generic Factory

Implement Factory pattern using generics     public interface IDoWork   {       string DoWork();   }     Declare an Interface first by abstracting the common  functionality    Here I am taking the example of DoWork     public class Manager : IDoWork   {     public string DoWork()     {         return "Manager Manages School" ;     }   }     Implement the IDoWork in concrete classes as shown      public class Teacher : IDoWork     {         public string DoWork()         {             return "Teacher teaches student in school" ;         }     }     public class Student : IDoWork     {         public string DoWork()         {             return "Study in school" ;         }     } This class will actually create an instance of the concrete class so that you can work on that        object further     public class FactoryDemo     {         public T Create
7 comments
Read more

How to enable windows authentication in PostgreSQL

1.     Steps to create user or role in PostgreSQL ·         Open pgAdmin III ·         Login to PostgreSQL database ·         Select “Login Roles” and right click on mouse to view the context menu ·         Select “New Login Role” from context menu ·         Enter desired user name in “Role name” text box ·         Select “Definition” tab in “New Login Role” window ·         Enter desired Password in the given text box ·         Select “Role privileges” tab in “New Login Role” window ·         Select the privileges for the entered user or role ·         Select “SQL” tab in “New Login Role” window ·         This will display the auto generated script ·         Review the script and click on “OK” button ·         Now in the “Login Roles” the newly created role or user “newUser” is displayed ·         Now in pgAdmin III object browser select the database to which the newly created user should be ma
Post a Comment
Read more

UML - Association, Aggregation, Composition, Generalization, Specialization, Realization and Dependency

Association Association is a simple relationship between two classes. For example A relationship between Professor Class and Student class is known as Association. Both Classes can exist without each other, so Professor and Student are two independent classes. In this kind of relationships there will not be any owner class. Both classes have their own life cycle. UML Notation:     Aggregation Aggregation is a special type of Association. It is known as “Has-A” relationship. For example A Department class can contain Professor Class. Here Department class is owner class. Here in this relationship even after deleting Department class, Professor Class can exits. UML Notation: Composition Composition is a special type of Aggregation. It is known as “Is-A” relationship. For example A University Class has many Department class. Here University and Department objects are dependent on each other. If we delete University cl
1 comment
Read more