GZipStream Constructeurs

Source:

GZipStream.cs

Source:

GZipStream.cs

Source:

GZipStream.cs

public:
 GZipStream(System::IO::Stream ^ stream, System::IO::Compression::CompressionLevel compressionLevel);

public GZipStream (System.IO.Stream stream, System.IO.Compression.CompressionLevel compressionLevel);

new System.IO.Compression.GZipStream : System.IO.Stream * System.IO.Compression.CompressionLevel -> System.IO.Compression.GZipStream

Public Sub New (stream As Stream, compressionLevel As CompressionLevel)

Paramètres

Exceptions

Remarques

Vous utilisez ce constructeur lorsque vous souhaitez spécifier si l’efficacité ou la vitesse de compression est plus importante pour une instance de la classe GZipStream.

Cette surcharge de constructeur utilise le mode de compression Compress. Pour définir le mode de compression sur une autre valeur, utilisez la surcharge GZipStream(Stream, CompressionMode) ou GZipStream(Stream, CompressionMode, Boolean).

Source:

GZipStream.cs

Source:

GZipStream.cs

Source:

GZipStream.cs

public:
 GZipStream(System::IO::Stream ^ stream, System::IO::Compression::CompressionMode mode);

public GZipStream (System.IO.Stream stream, System.IO.Compression.CompressionMode mode);

new System.IO.Compression.GZipStream : System.IO.Stream * System.IO.Compression.CompressionMode -> System.IO.Compression.GZipStream

Public Sub New (stream As Stream, mode As CompressionMode)

Paramètres

Exceptions

Exemples

L’exemple suivant montre comment définir le mode de compression lors de la création d’un objet GZipStream.

using System;
using System.IO;
using System.IO.Compression;

public class FileCompressionModeExample
{
    private const string Message = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.";
    private const string OriginalFileName = "original.txt";
    private const string CompressedFileName = "compressed.gz";
    private const string DecompressedFileName = "decompressed.txt";

    public static void Run()
    {
        CreateFileToCompress();
        CompressFile();
        DecompressFile();
        PrintResults();
        DeleteFiles();

        /*
         Output:

            The original file 'original.txt' is 445 bytes. Contents: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."

            The compressed file 'compressed.gz' is 283 bytes.

            The decompressed file 'decompressed.txt' is 445 bytes. Contents: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
         */
    }

    private static void CreateFileToCompress() => File.WriteAllText(OriginalFileName, Message);

    private static void CompressFile()
    {
        using FileStream originalFileStream = File.Open(OriginalFileName, FileMode.Open);
        using FileStream compressedFileStream = File.Create(CompressedFileName);
        using var compressor = new GZipStream(compressedFileStream, CompressionMode.Compress);
        originalFileStream.CopyTo(compressor);
    }

    private static void DecompressFile()
    {
        using FileStream compressedFileStream = File.Open(CompressedFileName, FileMode.Open);
        using FileStream outputFileStream = File.Create(DecompressedFileName);
        using var decompressor = new GZipStream(compressedFileStream, CompressionMode.Decompress);
        decompressor.CopyTo(outputFileStream);
    }

    private static void PrintResults()
    {
        long originalSize = new FileInfo(OriginalFileName).Length;
        long compressedSize = new FileInfo(CompressedFileName).Length;
        long decompressedSize = new FileInfo(DecompressedFileName).Length;

        Console.WriteLine($"The original file '{OriginalFileName}' is {originalSize} bytes. Contents: \"{File.ReadAllText(OriginalFileName)}\"");
        Console.WriteLine($"The compressed file '{CompressedFileName}' is {compressedSize} bytes.");
        Console.WriteLine($"The decompressed file '{DecompressedFileName}' is {decompressedSize} bytes. Contents: \"{File.ReadAllText(DecompressedFileName)}\"");
    }

    private static void DeleteFiles()
    {
        File.Delete(OriginalFileName);
        File.Delete(CompressedFileName);
        File.Delete(DecompressedFileName);
    }
}

open System.IO
open System.IO.Compression

let message =
    "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."

let OriginalFileName = "original.txt"
let CompressedFileName = "compressed.gz"
let DecompressedFileName = "decompressed.txt"

let createFileToCompress () =
    File.WriteAllText(OriginalFileName, message)

let compressFile () =
    use originalFileStream = File.Open(OriginalFileName, FileMode.Open)
    use compressedFileStream = File.Create CompressedFileName
    use compressor = new GZipStream(compressedFileStream, CompressionMode.Compress)
    originalFileStream.CopyTo compressor

let decompressFile () =
    use compressedFileStream = File.Open(CompressedFileName, FileMode.Open)
    use outputFileStream = File.Create DecompressedFileName
    use decompressor = new GZipStream(compressedFileStream, CompressionMode.Decompress)
    decompressor.CopyTo outputFileStream

let printResults () =
    let originalSize = FileInfo(OriginalFileName).Length
    let compressedSize = FileInfo(CompressedFileName).Length
    let decompressedSize = FileInfo(DecompressedFileName).Length

    printfn
        $"The original file '{OriginalFileName}' weighs {originalSize} bytes. Contents: \"{File.ReadAllText OriginalFileName}\""

    printfn $"The compressed file '{CompressedFileName}' weighs {compressedSize} bytes."

    printfn
        $"The decompressed file '{DecompressedFileName}' weighs {decompressedSize} bytes. Contents: \"{File.ReadAllText DecompressedFileName}\""

let deleteFiles () =
    File.Delete OriginalFileName
    File.Delete CompressedFileName
    File.Delete DecompressedFileName

createFileToCompress ()
compressFile ()
decompressFile ()
printResults ()
deleteFiles ()

// Output:
//     The original file 'original.txt' weighs 445 bytes. Contents: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
//
//     The compressed file 'compressed.gz' weighs 283 bytes.
//
//     The decompressed file 'decompressed.txt' weighs 445 bytes. Contents: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."

Imports System
Imports System.IO
Imports System.IO.Compression

Public Class FileCompressionModeExample
    Private Const Message As String = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
    Private Const OriginalFileName As String = "original.txt"
    Private Const CompressedFileName As String = "compressed.gz"
    Private Const DecompressedFileName As String = "decompressed.txt"

    Public Shared Sub Main()
        CreateFileToCompress()
        CompressFile()
        DecompressFile()
        PrintResults()
        DeleteFiles()

        ' Output:
        '   The original file 'original.txt' weighs 445 bytes. Contents: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."

        '   The compressed file 'compressed.gz' weighs 283 bytes.

        '   The decompressed file 'decompressed.txt' weighs 445 bytes. Contents: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
    End Sub

    Private Shared Sub CreateFileToCompress()
        File.WriteAllText(OriginalFileName, Message)
    End Sub

    Private Shared Sub CompressFile()
        Using originalFileStream As FileStream = File.Open(OriginalFileName, FileMode.Open)
            Using compressedFileStream As FileStream = File.Create(CompressedFileName)
                Using compressor = New GZipStream(compressedFileStream, CompressionMode.Compress)
                    originalFileStream.CopyTo(compressor)
                End Using
            End Using
        End Using
    End Sub

    Private Shared Sub DecompressFile()
        Using compressedFileStream As FileStream = File.Open(CompressedFileName, FileMode.Open)
            Using outputFileStream As FileStream = File.Create(DecompressedFileName)
                Using decompressor = New GZipStream(compressedFileStream, CompressionMode.Decompress)
                    decompressor.CopyTo(outputFileStream)
                End Using
            End Using
        End Using
    End Sub

    Private Shared Sub PrintResults()
        Dim originalSize As Long = New FileInfo(OriginalFileName).Length
        Dim compressedSize As Long = New FileInfo(CompressedFileName).Length
        Dim decompressedSize As Long = New FileInfo(DecompressedFileName).Length

        Console.WriteLine($"The original file '{OriginalFileName}' weighs {originalSize} bytes. Contents: ""{File.ReadAllText(OriginalFileName)}""")
        Console.WriteLine($"The compressed file '{CompressedFileName}' weighs {compressedSize} bytes.")
        Console.WriteLine($"The decompressed file '{DecompressedFileName}' weighs {decompressedSize} bytes. Contents: ""{File.ReadAllText(DecompressedFileName)}""")
    End Sub

    Private Shared Sub DeleteFiles()
        File.Delete(OriginalFileName)
        File.Delete(CompressedFileName)
        File.Delete(DecompressedFileName)
    End Sub
End Class

Remarques

Par défaut, GZipStream possède le flux sous-jacent. Par conséquent, la fermeture du paramètre stream ferme également le flux sous-jacent. Notez que l’état du flux sous-jacent peut affecter la facilité d’utilisation du flux. En outre, aucune vérification explicite n’est effectuée. Par conséquent, aucune exception supplémentaire n’est levée lors de la création de la nouvelle instance.

Si une instance de la classe GZipStream est créée avec le paramètre mode égal à Compress et qu’aucune autre action ne se produit, le flux s’affiche sous forme de fichier compressé valide et vide.

Par défaut, le niveau de compression est défini sur Optimal lorsque le mode de compression est Compress.

Source:

GZipStream.cs

Source:

GZipStream.cs

Source:

GZipStream.cs

public:
 GZipStream(System::IO::Stream ^ stream, System::IO::Compression::CompressionLevel compressionLevel, bool leaveOpen);

public GZipStream (System.IO.Stream stream, System.IO.Compression.CompressionLevel compressionLevel, bool leaveOpen);

new System.IO.Compression.GZipStream : System.IO.Stream * System.IO.Compression.CompressionLevel * bool -> System.IO.Compression.GZipStream

Public Sub New (stream As Stream, compressionLevel As CompressionLevel, leaveOpen As Boolean)

Paramètres

Exceptions

Exemples

L’exemple suivant montre comment définir le niveau de compression lors de la création d’un objet GZipStream et comment laisser le flux ouvert.

using System;
using System.IO;
using System.IO.Compression;
using System.Text;

public static class MemoryWriteReadExample
{
    private const string Message = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.";
    private static readonly byte[] s_messageBytes = Encoding.ASCII.GetBytes(Message);

    public static void Run()
    {
        Console.WriteLine($"The original string length is {s_messageBytes.Length} bytes.");
        using var stream = new MemoryStream();
        CompressBytesToStream(stream);
        Console.WriteLine($"The compressed stream length is {stream.Length} bytes.");
        int decompressedLength = DecompressStreamToBytes(stream);
        Console.WriteLine($"The decompressed string length is {decompressedLength} bytes, same as the original length.");
        /*
         Output:
            The original string length is 445 bytes.
            The compressed stream length is 282 bytes.
            The decompressed string length is 445 bytes, same as the original length.
        */
    }

    private static void CompressBytesToStream(Stream stream)
    {
        using var compressor = new GZipStream(stream, CompressionLevel.SmallestSize, leaveOpen: true);
        compressor.Write(s_messageBytes, 0, s_messageBytes.Length);
    }

    private static int DecompressStreamToBytes(Stream stream)
    {
        stream.Position = 0;
        int bufferSize = 512;
        byte[] buffer = new byte[bufferSize];
        using var gzipStream = new GZipStream(stream, CompressionMode.Decompress);

        int totalRead = 0;
        while (totalRead < buffer.Length)
        {
            int bytesRead = gzipStream.Read(buffer.AsSpan(totalRead));
            if (bytesRead == 0) break;
            totalRead += bytesRead;
        }

        return totalRead;
    }
}

open System.IO
open System.IO.Compression
open System.Text

let message =
    "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."

let s_messageBytes = Encoding.ASCII.GetBytes message

let compressBytesToStream stream =
    use compressor =
        new GZipStream(stream, CompressionLevel.SmallestSize, leaveOpen = true)

    compressor.Write(s_messageBytes, 0, s_messageBytes.Length)

let decompressStreamToBytes (stream: Stream) =
    stream.Position <- 0
    let bufferSize = 512
    let decompressedBytes = Array.zeroCreate bufferSize
    use decompressor = new GZipStream(stream, CompressionMode.Decompress)
    decompressor.Read(decompressedBytes, 0, bufferSize)

[<EntryPoint>]
let main _ =
    printfn $"The original string length is {s_messageBytes.Length} bytes."
    use stream = new MemoryStream()
    compressBytesToStream stream
    printfn $"The compressed stream length is {stream.Length} bytes."
    let decompressedLength = decompressStreamToBytes stream
    printfn $"The decompressed string length is {decompressedLength} bytes, same as the original length."
    0

// Output:
//     The original string length is 445 bytes.
//     The compressed stream length is 282 bytes.
//     The decompressed string length is 445 bytes, same as the original length.

Imports System.IO
Imports System.IO.Compression
Imports System.Text

Module MemoryWriteReadExample
    Private Const Message As String = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
    Private ReadOnly s_messageBytes As Byte() = Encoding.ASCII.GetBytes(Message)

    Sub Main()
        Console.WriteLine($"The original string length is {s_messageBytes.Length} bytes.")

        Using stream = New MemoryStream()
            CompressBytesToStream(stream)
            Console.WriteLine($"The compressed stream length is {stream.Length} bytes.")
            Dim decompressedLength As Integer = DecompressStreamToBytes(stream)
            Console.WriteLine($"The decompressed string length is {decompressedLength} bytes, same as the original length.")
        End Using
        ' Output:
        '   The original string length is 445 bytes.
        '   The compressed stream length is 282 bytes.
        '   The decompressed string length is 445 bytes, same as the original length.
    End Sub

    Private Sub CompressBytesToStream(ByVal stream As Stream)
        Using compressor = New GZipStream(stream, CompressionLevel.SmallestSize, leaveOpen:=True)
            compressor.Write(s_messageBytes, 0, s_messageBytes.Length)
        End Using
    End Sub

    Private Function DecompressStreamToBytes(ByVal stream As Stream) As Integer
        stream.Position = 0
        Dim bufferSize As Integer = 512
        Dim decompressedBytes As Byte() = New Byte(bufferSize - 1) {}
        Using decompressor = New GZipStream(stream, CompressionMode.Decompress)
            Dim length As Integer = decompressor.Read(decompressedBytes, 0, bufferSize)
            Return length
        End Using
    End Function
End Module

Remarques

Vous utilisez ce constructeur lorsque vous souhaitez spécifier si l’efficacité ou la vitesse de compression est plus importante pour une instance de la classe GZipStream, et s’il faut laisser l’objet de flux ouvert après la suppression de l’objet GZipStream.

Cette surcharge de constructeur utilise le mode de compression Compress. Pour définir le mode de compression sur une autre valeur, utilisez la surcharge GZipStream(Stream, CompressionMode) ou GZipStream(Stream, CompressionMode, Boolean).

Source:

GZipStream.cs

Source:

GZipStream.cs

Source:

GZipStream.cs

public:
 GZipStream(System::IO::Stream ^ stream, System::IO::Compression::CompressionMode mode, bool leaveOpen);

public GZipStream (System.IO.Stream stream, System.IO.Compression.CompressionMode mode, bool leaveOpen);

new System.IO.Compression.GZipStream : System.IO.Stream * System.IO.Compression.CompressionMode * bool -> System.IO.Compression.GZipStream

Public Sub New (stream As Stream, mode As CompressionMode, leaveOpen As Boolean)

Paramètres

Exceptions

Remarques

Par défaut, GZipStream possède le flux sous-jacent. Par conséquent, la fermeture du paramètre stream ferme également le flux sous-jacent. L’état du flux sous-jacent peut affecter la facilité d’utilisation du flux. En outre, aucune vérification explicite n’est effectuée. Par conséquent, aucune exception supplémentaire n’est levée lors de la création de la nouvelle instance.

Si une instance de la classe GZipStream est créée avec le paramètre mode égal à Compress et qu’aucune autre action ne se produit, le flux s’affiche sous forme de fichier compressé valide et vide.

Par défaut, le niveau de compression est défini sur Optimal lorsque le mode de compression est Compress.

public GZipStream (System.IO.Stream stream, System.IO.Compression.ZLibCompressionOptions compressionOptions, bool leaveOpen = false);

new System.IO.Compression.GZipStream : System.IO.Stream * System.IO.Compression.ZLibCompressionOptions * bool -> System.IO.Compression.GZipStream

Public Sub New (stream As Stream, compressionOptions As ZLibCompressionOptions, Optional leaveOpen As Boolean = false)

Paramètres

Exceptions