ToBase64Transform Classe

Definizione

Consente di convertire un oggetto CryptoStream in Base 64.Converts a CryptoStream to base 64.

public ref class ToBase64Transform : System::Security::Cryptography::ICryptoTransform
[System.Runtime.InteropServices.ComVisible(true)]
public class ToBase64Transform : System.Security.Cryptography.ICryptoTransform
type ToBase64Transform = class
    interface ICryptoTransform
    interface IDisposable
Public Class ToBase64Transform
Implements ICryptoTransform
Ereditarietà
ToBase64Transform
Attributi
Implementazioni

Esempi

Nell'esempio di codice riportato di seguito viene illustrato come utilizzare ToBase64Transform i membri della classe.The following code example demonstrates how to use members of the ToBase64Transform class.

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.Base 64 Content-Transfer-Encoding represents arbitrary bit sequences in a form that is not human readable.

Costruttori

ToBase64Transform()

Inizializza una nuova istanza della classe ToBase64Transform.Initializes a new instance of the ToBase64Transform class.

Proprietà

CanReuseTransform

Ottiene un valore che indica se è possibile riutilizzare la trasformazione corrente.Gets a value indicating whether the current transform can be reused.

CanTransformMultipleBlocks

Ottiene un valore che indica se è possibile trasformare più blocchi.Gets a value that indicates whether multiple blocks can be transformed.

InputBlockSize

Ottiene la dimensione del blocco di input.Gets the input block size.

OutputBlockSize

Ottiene la dimensione del blocco di output.Gets the output block size.

Metodi

Clear()

Rilascia tutte le risorse usate da ToBase64Transform.Releases all resources used by the ToBase64Transform.

Dispose()

Rilascia tutte le risorse usate dall'istanza corrente della classe ToBase64Transform.Releases all resources used by the current instance of the ToBase64Transform class.

Dispose(Boolean)

Rilascia le risorse non gestite usate da ToBase64Transform e, facoltativamente, le risorse gestite.Releases the unmanaged resources used by the ToBase64Transform and optionally releases the managed resources.

Equals(Object)

Determina se l'oggetto specificato è uguale all'oggetto corrente.Determines whether the specified object is equal to the current object.

(Ereditato da Object)
Finalize()

Consente di liberare le risorse non gestite utilizzate dalla classe ToBase64Transform.Releases the unmanaged resources used by the ToBase64Transform.

GetHashCode()

Funge da funzione hash predefinita.Serves as the default hash function.

(Ereditato da Object)
GetType()

Ottiene l'oggetto Type dell'istanza corrente.Gets the Type of the current instance.

(Ereditato da Object)
MemberwiseClone()

Crea una copia superficiale dell'oggetto Object corrente.Creates a shallow copy of the current Object.

(Ereditato da Object)
ToString()

Restituisce una stringa che rappresenta l'oggetto corrente.Returns a string that represents the current object.

(Ereditato da Object)
TransformBlock(Byte[], Int32, Int32, Byte[], Int32)

Consente di convertire l'area specificata della matrice di byte di input in Base 64 e di copiare il risultato nell'area specificata della matrice di byte di output.Converts the specified region of the input byte array to base 64 and copies the result to the specified region of the output byte array.

TransformFinalBlock(Byte[], Int32, Int32)

Consente di convertire l'area definita della matrice di byte specificata in Base 64.Converts the specified region of the specified byte array to base 64.

Implementazioni dell'interfaccia esplicita

IDisposable.Dispose()

Consente di liberare le risorse non gestite utilizzate dalla classe ToBase64Transform.Releases the unmanaged resources used by the ToBase64Transform.

Si applica a

Vedi anche