ToBase64Transform Classe

Definizione

Spazio dei nomi:

System.Security.Cryptography

Assembly:

System.Security.Cryptography.dll

Origine:

Base64Transforms.cs

Converte un oggetto CryptoStream in Base 64.

public ref class ToBase64Transform : IDisposable, System::Security::Cryptography::ICryptoTransform

public class ToBase64Transform : IDisposable, System.Security.Cryptography.ICryptoTransform

type ToBase64Transform = class
    interface IDisposable
    interface ICryptoTransform

Public Class ToBase64Transform
Implements ICryptoTransform, IDisposable

Ereditarietà

Object

ToBase64Transform

Implementazioni

IDisposable ICryptoTransform

Esempio

Nell'esempio di codice seguente viene illustrato come usare i membri della ToBase64Transform classe .

using namespace System;
using namespace System::IO;
using namespace System::Security::Cryptography;

ref class Members
{
public:
   [STAThread]
   static void Main()
   {
      String^ appPath = (String::Concat(
         System::IO::Directory::GetCurrentDirectory(), L"\\" ));
      
      // Insert your file names into this method call.
      EncodeFromFile( String::Concat( appPath, L"members.cpp" ),
         String::Concat( appPath, L"members.enc" ) );
      Console::WriteLine( L"This sample completed successfully; "
         L"press Enter to exit." );
      Console::ReadLine();
   }

private:
   // Read in the specified source file and write out an encoded target file.
   static void EncodeFromFile( String^ sourceFile, String^ targetFile )
   {
      // Verify members.cpp exists at the specified directory.
      if (  !File::Exists( sourceFile ) )
      {
         Console::Write( L"Unable to locate source file located at " );
         Console::WriteLine( L"{0}.", sourceFile );
         Console::Write( L"Please correct the path and run the " );
         Console::WriteLine( L"sample again." );
         return;
      }

      // Retrieve the input and output file streams.
      FileStream^ inputFileStream = gcnew FileStream(
         sourceFile,FileMode::Open,FileAccess::Read );
      FileStream^ outputFileStream = gcnew FileStream(
         targetFile,FileMode::Create,FileAccess::Write );

      // Create a new ToBase64Transform object to convert to base 64.
      ToBase64Transform^ base64Transform = gcnew ToBase64Transform;

      // Create a new byte array with the size of the output block size.
      array<Byte>^outputBytes = gcnew array<Byte>(
         base64Transform->OutputBlockSize);

      // Retrieve the file contents into a byte array.
      array<Byte>^inputBytes = gcnew array<Byte>(inputFileStream->Length);
      inputFileStream->Read( inputBytes, 0, inputBytes->Length );

      // Verify that multiple blocks can not be transformed.
      if (  !base64Transform->CanTransformMultipleBlocks )
      {
         // Initializie the offset size.
         int inputOffset = 0;

         // Iterate through inputBytes transforming by blockSize.
         int inputBlockSize = base64Transform->InputBlockSize;
         while ( inputBytes->Length - inputOffset > inputBlockSize )
         {
            base64Transform->TransformBlock(
               inputBytes,
               inputOffset,
               inputBytes->Length - inputOffset,
               outputBytes,
               0 );

            inputOffset += base64Transform->InputBlockSize;
            outputFileStream->Write(
               outputBytes,
               0,
               base64Transform->OutputBlockSize );
         }
         
         // Transform the final block of data.
         outputBytes = base64Transform->TransformFinalBlock(
            inputBytes,
            inputOffset,
            inputBytes->Length - inputOffset );
         outputFileStream->Write( outputBytes, 0, outputBytes->Length );
         Console::WriteLine( L"Created encoded file at {0}", targetFile );
      }

      // Determine if the current transform can be reused.
      if (  !base64Transform->CanReuseTransform )
      {
         // Free up any used resources.
         base64Transform->Clear();
      }

      // Close file streams.
      inputFileStream->Close();
      outputFileStream->Close();
   }
};

int main()
{
   Members::Main();
}

//
// This sample produces the following output:
//
// Created encoded file at C:\ConsoleApplication1\\membersvcs.enc
// This sample completed successfully; press Enter to exit.

using System;
using System.IO;
using System.Security.Cryptography;

class Members
{
    [STAThread]
    static void Main(string[] args)
    {
        string appPath = (System.IO.Directory.GetCurrentDirectory() + "\\");

        // Insert your file names into this method call.
        EncodeFromFile(appPath + "members.cs", appPath + "members.enc");

        Console.WriteLine("This sample completed successfully; " +
            "press Enter to exit.");
        Console.ReadLine();
    }

    // Read in the specified source file and write out an encoded target file.
    private static void EncodeFromFile(string sourceFile, string targetFile) 
    {
        // Verify members.cs exists at the specified directory.
        if (!File.Exists(sourceFile))
        {
            Console.Write("Unable to locate source file located at ");
            Console.WriteLine(sourceFile + ".");
            Console.Write("Please correct the path and run the ");
            Console.WriteLine("sample again.");
            return;
        }

        // Retrieve the input and output file streams.
        FileStream inputFileStream = 
            new FileStream(sourceFile, FileMode.Open, FileAccess.Read);
        FileStream outputFileStream = 
            new FileStream(targetFile, FileMode.Create, FileAccess.Write);

        // Create a new ToBase64Transform object to convert to base 64.
        ToBase64Transform base64Transform = new ToBase64Transform();

        // Create a new byte array with the size of the output block size.
        byte[] outputBytes = new byte[base64Transform.OutputBlockSize];

        // Retrieve the file contents into a byte array.
        byte[] inputBytes = new byte[inputFileStream.Length];
        inputFileStream.Read(inputBytes, 0, inputBytes.Length);

        // Verify that multiple blocks can not be transformed.
        if (!base64Transform.CanTransformMultipleBlocks)
        {
            // Initializie the offset size.
            int inputOffset = 0;

            // Iterate through inputBytes transforming by blockSize.
            int inputBlockSize = base64Transform.InputBlockSize;

            while(inputBytes.Length - inputOffset > inputBlockSize)
            {
                base64Transform.TransformBlock(
                    inputBytes,
                    inputOffset,
                    inputBytes.Length - inputOffset,
                    outputBytes,
                    0);

                inputOffset += base64Transform.InputBlockSize;
                outputFileStream.Write(
                    outputBytes, 
                    0, 
                    base64Transform.OutputBlockSize);
            }

            // Transform the final block of data.
            outputBytes = base64Transform.TransformFinalBlock(
                inputBytes,
                inputOffset,
                inputBytes.Length - inputOffset);

            outputFileStream.Write(outputBytes, 0, outputBytes.Length);
            Console.WriteLine("Created encoded file at " + targetFile);
        }

        // Determine if the current transform can be reused.
        if (!base64Transform.CanReuseTransform)
        {
            // Free up any used resources.
            base64Transform.Clear();
        }

        // Close file streams.
        inputFileStream.Close();
        outputFileStream.Close();
    }
}
//
// This sample produces the following output:
//
// Created encoded file at C:\ConsoleApplication1\\membersvcs.enc
// This sample completed successfully; press Enter to exit.

Imports System.IO
Imports System.Security.Cryptography

Public Class Form1
    Inherits System.Windows.Forms.Form

    ' Event handler for Run button.
    Private Sub Button1_Click( _
        ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles Button1.Click

        tbxOutput.Cursor = Cursors.WaitCursor
        tbxOutput.Text = ""

        Dim appPath As String
        appPath = (System.IO.Directory.GetCurrentDirectory() + "\\")

        ' Insert your file names into this method call.
        EncodeFromFile(appPath + "members.vb", appPath + "membersvb.enc")

        ' Reset the cursor and conclude application.
        tbxOutput.AppendText(vbCrLf + "This sample completed " + _
            "successfully; press Exit to continue.")
        tbxOutput.Cursor = Cursors.Default
    End Sub

    ' Read in the specified source file and write out an encoded target file.
    Private Sub EncodeFromFile( _
        ByVal sourceFile As String, _
        ByVal targetFile As String)

        ' Verify members.cs exists at the specified directory.
        If (Not File.Exists(sourceFile)) Then
            tbxOutput.AppendText("Unable to locate source file located at ")
            tbxOutput.AppendText(sourceFile + ". Please correct the path ")
            tbxOutput.AppendText("and run the sample again.")

            Exit Sub
        End If

        ' Retrieve the input and output file streams.
        Dim inputFileStream As New FileStream( _
            sourceFile, FileMode.Open, FileAccess.Read)
        Dim outputFileStream As New FileStream( _
            targetFile, FileMode.Create, FileAccess.Write)

        ' Create a new ToBase64Transform object to convert to base 64.
        Dim base64Transform As New ToBase64Transform

        ' Create a new byte array with the size of the output block size.
        Dim outputBytes(base64Transform.OutputBlockSize) As Byte

        ' Retrieve the file contents into a byte array.
        Dim inputBytes(inputFileStream.Length) As Byte
        inputFileStream.Read(inputBytes, 0, inputBytes.Length)

        ' Verify that multiple blocks can not be transformed.
        If (Not base64Transform.CanTransformMultipleBlocks) Then
            ' Initializie the offset size.
            Dim inputOffset As Integer = 0

            ' Iterate through inputBytes transforming by blockSize.
            Dim inputBlockSize As Integer = base64Transform.InputBlockSize

            While (inputBytes.Length - inputOffset > inputBlockSize)
                base64Transform.TransformBlock( _
                    inputBytes, _
                    inputOffset, _
                    inputBytes.Length - inputOffset, _
                    outputBytes, _
                    0)

                inputOffset += base64Transform.InputBlockSize
                outputFileStream.Write(outputBytes, _
                    0, _
                    base64Transform.OutputBlockSize)
            End While

            ' Transform the final block of data.
            outputBytes = base64Transform.TransformFinalBlock( _
                inputBytes, _
                inputOffset, _
                inputBytes.Length - inputOffset)

            outputFileStream.Write(outputBytes, 0, outputBytes.Length)
            tbxOutput.AppendText("Created encoded file at " + targetFile)
        End If

        ' Determine if the current transform can be reused.
        If (Not base64Transform.CanReuseTransform) Then
            ' Free up any used resources.
            base64Transform.Clear()
        End If

        ' Close file streams.
        inputFileStream.Close()
        outputFileStream.Close()
    End Sub

    ' Event handler for Exit button.
    Private Sub Button2_Click( _
        ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles Button2.Click

        Application.Exit()
    End Sub
#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Windows Form Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Required by the Windows Form Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.  
    'Do not modify it using the code editor.
    Friend WithEvents Panel2 As System.Windows.Forms.Panel
    Friend WithEvents Panel1 As System.Windows.Forms.Panel
    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents Button2 As System.Windows.Forms.Button
    Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox
    <System.Diagnostics.DebuggerStepThrough()> _
    Private Sub InitializeComponent()
        Me.Panel2 = New System.Windows.Forms.Panel
        Me.Button1 = New System.Windows.Forms.Button
        Me.Button2 = New System.Windows.Forms.Button
        Me.Panel1 = New System.Windows.Forms.Panel
        Me.tbxOutput = New System.Windows.Forms.RichTextBox
        Me.Panel2.SuspendLayout()
        Me.Panel1.SuspendLayout()
        Me.SuspendLayout()
        '
        'Panel2
        '
        Me.Panel2.Controls.Add(Me.Button1)
        Me.Panel2.Controls.Add(Me.Button2)
        Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom
        Me.Panel2.DockPadding.All = 20
        Me.Panel2.Location = New System.Drawing.Point(0, 320)
        Me.Panel2.Name = "Panel2"
        Me.Panel2.Size = New System.Drawing.Size(616, 64)
        Me.Panel2.TabIndex = 1
        '
        'Button1
        '
        Me.Button1.Dock = System.Windows.Forms.DockStyle.Right
        Me.Button1.Font = New System.Drawing.Font( _
            "Microsoft Sans Serif", _
            9.0!, _
            System.Drawing.FontStyle.Regular, _
            System.Drawing.GraphicsUnit.Point, _
            CType(0, Byte))
        Me.Button1.Location = New System.Drawing.Point(446, 20)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(75, 24)
        Me.Button1.TabIndex = 2
        Me.Button1.Text = "&Run"
        '
        'Button2
        '
        Me.Button2.Dock = System.Windows.Forms.DockStyle.Right
        Me.Button2.Font = New System.Drawing.Font( _
            "Microsoft Sans Serif", _
            9.0!, _
            System.Drawing.FontStyle.Regular, _
            System.Drawing.GraphicsUnit.Point, _
            CType(0, Byte))
        Me.Button2.Location = New System.Drawing.Point(521, 20)
        Me.Button2.Name = "Button2"
        Me.Button2.Size = New System.Drawing.Size(75, 24)
        Me.Button2.TabIndex = 3
        Me.Button2.Text = "E&xit"
        '
        'Panel1
        '
        Me.Panel1.Controls.Add(Me.tbxOutput)
        Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill
        Me.Panel1.DockPadding.All = 20
        Me.Panel1.Location = New System.Drawing.Point(0, 0)
        Me.Panel1.Name = "Panel1"
        Me.Panel1.Size = New System.Drawing.Size(616, 320)
        Me.Panel1.TabIndex = 2
        '
        'tbxOutput
        '
        Me.tbxOutput.AccessibleDescription = _
            "Displays output from application."
        Me.tbxOutput.AccessibleName = "Output textbox."
        Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill
        Me.tbxOutput.Location = New System.Drawing.Point(20, 20)
        Me.tbxOutput.Name = "tbxOutput"
        Me.tbxOutput.Size = New System.Drawing.Size(576, 280)
        Me.tbxOutput.TabIndex = 1
        Me.tbxOutput.Text = "Click the Run button to run the application."
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
        Me.ClientSize = New System.Drawing.Size(616, 384)
        Me.Controls.Add(Me.Panel1)
        Me.Controls.Add(Me.Panel2)
        Me.Name = "Form1"
        Me.Text = "ToBase64Transform"
        Me.Panel2.ResumeLayout(False)
        Me.Panel1.ResumeLayout(False)
        Me.ResumeLayout(False)

    End Sub

#End Region
End Class
'
' This sample produces the following output:
'
' Created encoded file at C:\WindowsApplication1\\membersvb.enc
' This sample completed successfully; press Exit to continue.

Commenti

Base 64 Content-Transfer-Encoding rappresenta sequenze di bit arbitrarie in un formato non leggibile.

Costruttori

ToBase64Transform()

Inizializza una nuova istanza della classe ToBase64Transform.

Proprietà

CanReuseTransform	Ottiene un valore che indica se è possibile riutilizzare la trasformazione corrente.
CanTransformMultipleBlocks	Ottiene un valore che indica se è possibile trasformare più blocchi.
InputBlockSize	Ottiene la dimensione del blocco di input.
OutputBlockSize	Ottiene la dimensione del blocco di output.

Metodi

Clear()	Rilascia tutte le risorse usate da ToBase64Transform.
Dispose()	Rilascia tutte le risorse usate dall'istanza corrente della classe ToBase64Transform.
Dispose(Boolean)	Rilascia le risorse non gestite usate da ToBase64Transform e, facoltativamente, le risorse gestite.
Equals(Object)	Determina se l'oggetto specificato è uguale all'oggetto corrente. (Ereditato da Object)
Finalize()	Rilascia le risorse non gestite utilizzate dall'oggetto ToBase64Transform.
GetHashCode()	Funge da funzione hash predefinita. (Ereditato da Object)
GetType()	Ottiene l'oggetto Type dell'istanza corrente. (Ereditato da Object)
MemberwiseClone()	Crea una copia superficiale dell'oggetto Object corrente. (Ereditato da Object)
ToString()	Restituisce una stringa che rappresenta l'oggetto corrente. (Ereditato da Object)
TransformBlock(Byte[], Int32, Int32, Byte[], Int32)	Converte l'area specificata della matrice di byte di input in Base 64 e copia il risultato nell'area specificata della matrice di byte di output.
TransformFinalBlock(Byte[], Int32, Int32)	Converte l'area definita della matrice di byte specificata in Base 64.

Vedi anche

• servizi crittografici