ToBase64Transform Class

Definition

Converts a CryptoStream to base 64.

C#
public class ToBase64Transform : IDisposable, System.Security.Cryptography.ICryptoTransform
C#
public class ToBase64Transform : System.Security.Cryptography.ICryptoTransform
C#
[System.Runtime.InteropServices.ComVisible(true)]
public class ToBase64Transform : System.Security.Cryptography.ICryptoTransform
Inheritance
ToBase64Transform
Attributes
Implements

Examples

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

C#
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.

Remarks

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

Constructors

ToBase64Transform()

Initializes a new instance of the ToBase64Transform class.

Properties

CanReuseTransform

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

CanTransformMultipleBlocks

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

InputBlockSize

Gets the input block size.

OutputBlockSize

Gets the output block size.

Methods

Clear()

Releases all resources used by the ToBase64Transform.

Dispose()

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

Dispose(Boolean)

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

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
Finalize()

Releases the unmanaged resources used by the ToBase64Transform.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)
TransformBlock(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.

TransformFinalBlock(Byte[], Int32, Int32)

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

Explicit Interface Implementations

IDisposable.Dispose()

Releases the unmanaged resources used by the ToBase64Transform.

Applies to

Product Versions
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

See also