ToBase64Transform Class

 

Converts a CryptoStream to base 64.

Namespace:   System.Security.Cryptography
Assembly:  mscorlib (in mscorlib.dll)

System.Object
  System.Security.Cryptography.ToBase64Transform

[ComVisibleAttribute(true)]
public class ToBase64Transform : ICryptoTransform, IDisposable

NameDescription
System_CAPS_pubmethodToBase64Transform()

Initializes a new instance of the ToBase64Transform class.

NameDescription
System_CAPS_pubpropertyCanReuseTransform

Gets a value indicating whether the current transform can be reused.

System_CAPS_pubpropertyCanTransformMultipleBlocks

Gets a value that indicates whether multiple blocks can be transformed.

System_CAPS_pubpropertyInputBlockSize

Gets the input block size.

System_CAPS_pubpropertyOutputBlockSize

Gets the output block size.

NameDescription
System_CAPS_pubmethodClear()

Releases all resources used by the ToBase64Transform.

System_CAPS_pubmethodDispose()

Releases all resources used by the current instance of the ToBase64Transform class.

System_CAPS_protmethodDispose(Boolean)

Releases the unmanaged resources used by the ToBase64Transform and optionally releases the managed resources.

System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethodFinalize()

Releases the unmanaged resources used by the ToBase64Transform.(Overrides Object.Finalize().)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_protmethodMemberwiseClone()

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

System_CAPS_pubmethodTransformBlock(Byte[], Int32, Int32, Byte[], Int32)

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.

System_CAPS_pubmethodTransformFinalBlock(Byte[], Int32, Int32)

Converts the specified region of the specified byte array to base 64.

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

The following code example demonstrates how to use members of the ToBase64Transform class.

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.

.NET Framework
Available since 1.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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