DESCryptoServiceProvider.CreateEncryptor Metoda
Definice
Důležité
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Vytvoří objekt symetrického encryptoru.
Přetížení
CreateEncryptor() |
Vytvoří objekt symetrického encryptoru s aktuální Key vlastností a inicializačním vektorem (IV). |
CreateEncryptor(Byte[], Byte[]) |
Vytvoří objekt šifrování symetrického standardu šifrování dat (DES) se zadaným klíčem (Key) a inicializačním vektorem (IV). |
CreateEncryptor()
public:
override System::Security::Cryptography::ICryptoTransform ^ CreateEncryptor();
public override System.Security.Cryptography.ICryptoTransform CreateEncryptor ();
override this.CreateEncryptor : unit -> System.Security.Cryptography.ICryptoTransform
Public Overrides Function CreateEncryptor () As ICryptoTransform
Návraty
Objekt symetrického šifrovače.
Poznámky
Pokud je null
aktuální Key vlastnost , GenerateKey je volána metoda pro vytvoření nového náhodného Keyobjektu . Pokud je null
aktuální IV vlastnost , GenerateIV je volána metoda pro vytvoření nového náhodného IVobjektu .
K dešifrování výsledku CreateDecryptor této metody použijte přetížení se stejným podpisem.
Platí pro
CreateEncryptor(Byte[], Byte[])
public:
override System::Security::Cryptography::ICryptoTransform ^ CreateEncryptor(cli::array <System::Byte> ^ rgbKey, cli::array <System::Byte> ^ rgbIV);
public override System.Security.Cryptography.ICryptoTransform CreateEncryptor (byte[] rgbKey, byte[]? rgbIV);
public override System.Security.Cryptography.ICryptoTransform CreateEncryptor (byte[] rgbKey, byte[] rgbIV);
override this.CreateEncryptor : byte[] * byte[] -> System.Security.Cryptography.ICryptoTransform
Public Overrides Function CreateEncryptor (rgbKey As Byte(), rgbIV As Byte()) As ICryptoTransform
Parametry
- rgbKey
- Byte[]
Tajný klíč, který se má použít pro symetrický algoritmus.
- rgbIV
- Byte[]
Inicializační vektor, který se má použít pro symetrický algoritmus.
Návraty
Objekt symetrického DES šifrovače.
Výjimky
Hodnota Mode vlastnosti je OFB.
-nebo-
Hodnota Mode vlastnosti je CFB a hodnota FeedbackSize vlastnosti není 8.
-nebo-
Byla použita neplatná velikost klíče.
-nebo-
Velikost klíče algoritmu nebyla k dispozici.
Příklady
Následující příklad kódu ukazuje, jak vytvořit a použít DESCryptoServiceProvider objekt k šifrování a dešifrování dat v souboru.
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
using namespace System::IO;
void EncryptTextToFile( String^ Data, String^ FileName, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create or open the specified file.
FileStream^ fStream = File::Open( FileName, FileMode::OpenOrCreate );
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream^ cStream = gcnew CryptoStream( fStream,(gcnew DESCryptoServiceProvider)->CreateEncryptor( Key, IV ),CryptoStreamMode::Write );
// Create a StreamWriter using the CryptoStream.
StreamWriter^ sWriter = gcnew StreamWriter( cStream );
// Write the data to the stream
// to encrypt it.
sWriter->WriteLine( Data );
// Close the streams and
// close the file.
sWriter->Close();
cStream->Close();
fStream->Close();
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
}
catch ( UnauthorizedAccessException^ e )
{
Console::WriteLine( "A file error occurred: {0}", e->Message );
}
}
String^ DecryptTextFromFile( String^ FileName, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create or open the specified file.
FileStream^ fStream = File::Open( FileName, FileMode::OpenOrCreate );
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream^ cStream = gcnew CryptoStream( fStream,(gcnew DESCryptoServiceProvider)->CreateDecryptor( Key, IV ),CryptoStreamMode::Read );
// Create a StreamReader using the CryptoStream.
StreamReader^ sReader = gcnew StreamReader( cStream );
// Read the data from the stream
// to decrypt it.
String^ val = sReader->ReadLine();
// Close the streams and
// close the file.
sReader->Close();
cStream->Close();
fStream->Close();
// Return the string.
return val;
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
return nullptr;
}
catch ( UnauthorizedAccessException^ e )
{
Console::WriteLine( "A file error occurred: {0}", e->Message );
return nullptr;
}
}
int main()
{
try
{
// Create a new DESCryptoServiceProvider object
// to generate a key and initialization vector (IV).
DESCryptoServiceProvider^ DESalg = gcnew DESCryptoServiceProvider;
// Create a string to encrypt.
String^ sData = "Here is some data to encrypt.";
String^ FileName = "CText.txt";
// Encrypt text to a file using the file name, key, and IV.
EncryptTextToFile( sData, FileName, DESalg->Key, DESalg->IV );
// Decrypt the text from a file using the file name, key, and IV.
String^ Final = DecryptTextFromFile( FileName, DESalg->Key, DESalg->IV );
// Display the decrypted string to the console.
Console::WriteLine( Final );
}
catch ( Exception^ e )
{
Console::WriteLine( e->Message );
}
}
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;
class DESCSPSample
{
static void Main()
{
try
{
// Create a new DESCryptoServiceProvider object
// to generate a key and initialization vector (IV).
DESCryptoServiceProvider DESalg = new DESCryptoServiceProvider();
// Create a string to encrypt.
string sData = "Here is some data to encrypt.";
string FileName = "CText.txt";
// Encrypt text to a file using the file name, key, and IV.
EncryptTextToFile(sData, FileName, DESalg.Key, DESalg.IV);
// Decrypt the text from a file using the file name, key, and IV.
string Final = DecryptTextFromFile(FileName, DESalg.Key, DESalg.IV);
// Display the decrypted string to the console.
Console.WriteLine(Final);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
public static void EncryptTextToFile(String Data, String FileName, byte[] Key, byte[] IV)
{
try
{
// Create or open the specified file.
FileStream fStream = File.Open(FileName,FileMode.OpenOrCreate);
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream cStream = new CryptoStream(fStream,
new DESCryptoServiceProvider().CreateEncryptor(Key,IV),
CryptoStreamMode.Write);
// Create a StreamWriter using the CryptoStream.
StreamWriter sWriter = new StreamWriter(cStream);
// Write the data to the stream
// to encrypt it.
sWriter.WriteLine(Data);
// Close the streams and
// close the file.
sWriter.Close();
cStream.Close();
fStream.Close();
}
catch(CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
}
catch(UnauthorizedAccessException e)
{
Console.WriteLine("A file error occurred: {0}", e.Message);
}
}
public static string DecryptTextFromFile(String FileName, byte[] Key, byte[] IV)
{
try
{
// Create or open the specified file.
FileStream fStream = File.Open(FileName, FileMode.OpenOrCreate);
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream cStream = new CryptoStream(fStream,
new DESCryptoServiceProvider().CreateDecryptor(Key,IV),
CryptoStreamMode.Read);
// Create a StreamReader using the CryptoStream.
StreamReader sReader = new StreamReader(cStream);
// Read the data from the stream
// to decrypt it.
string val = sReader.ReadLine();
// Close the streams and
// close the file.
sReader.Close();
cStream.Close();
fStream.Close();
// Return the string.
return val;
}
catch(CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
return null;
}
catch(UnauthorizedAccessException e)
{
Console.WriteLine("A file error occurred: {0}", e.Message);
return null;
}
}
}
Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
Module DESCSPSample
Sub Main()
Try
' Create a new DESCryptoServiceProvider object
' to generate a key and initialization vector (IV).
Dim DESalg As New DESCryptoServiceProvider
' Create a string to encrypt.
Dim sData As String = "Here is some data to encrypt."
Dim FileName As String = "CText.txt"
' Encrypt text to a file using the file name, key, and IV.
EncryptTextToFile(sData, FileName, DESalg.Key, DESalg.IV)
' Decrypt the text from a file using the file name, key, and IV.
Dim Final As String = DecryptTextFromFile(FileName, DESalg.Key, DESalg.IV)
' Display the decrypted string to the console.
Console.WriteLine(Final)
Catch e As Exception
Console.WriteLine(e.Message)
End Try
End Sub
Sub EncryptTextToFile(ByVal Data As String, ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte)
Try
' Create or open the specified file.
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
' Create a CryptoStream using the FileStream
' and the passed key and initialization vector (IV).
Dim cStream As New CryptoStream(fStream, _
New DESCryptoServiceProvider().CreateEncryptor(Key, IV), _
CryptoStreamMode.Write)
' Create a StreamWriter using the CryptoStream.
Dim sWriter As New StreamWriter(cStream)
' Write the data to the stream
' to encrypt it.
sWriter.WriteLine(Data)
' Close the streams and
' close the file.
sWriter.Close()
cStream.Close()
fStream.Close()
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Catch e As UnauthorizedAccessException
Console.WriteLine("A file error occurred: {0}", e.Message)
End Try
End Sub
Function DecryptTextFromFile(ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte) As String
Try
' Create or open the specified file.
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
' Create a CryptoStream using the FileStream
' and the passed key and initialization vector (IV).
Dim cStream As New CryptoStream(fStream, _
New DESCryptoServiceProvider().CreateDecryptor(Key, IV), _
CryptoStreamMode.Read)
' Create a StreamReader using the CryptoStream.
Dim sReader As New StreamReader(cStream)
' Read the data from the stream
' to decrypt it.
Dim val As String = sReader.ReadLine()
' Close the streams and
' close the file.
sReader.Close()
cStream.Close()
fStream.Close()
' Return the string.
Return val
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
Catch e As UnauthorizedAccessException
Console.WriteLine("A file error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
End Module
Následující příklad kódu ukazuje, jak vytvořit a použít DESCryptoServiceProvider objekt k šifrování a dešifrování dat v paměti.
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
using namespace System::IO;
array<Byte>^ EncryptTextToMemory( String^ Data, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create a MemoryStream.
MemoryStream^ mStream = gcnew MemoryStream;
// Create a CryptoStream using the MemoryStream
// and the passed key and initialization vector (IV).
CryptoStream^ cStream = gcnew CryptoStream( mStream,(gcnew DESCryptoServiceProvider)->CreateEncryptor( Key, IV ),CryptoStreamMode::Write );
// Convert the passed string to a byte array.
array<Byte>^toEncrypt = (gcnew ASCIIEncoding)->GetBytes( Data );
// Write the byte array to the crypto stream and flush it.
cStream->Write( toEncrypt, 0, toEncrypt->Length );
cStream->FlushFinalBlock();
// Get an array of bytes from the
// MemoryStream that holds the
// encrypted data.
array<Byte>^ret = mStream->ToArray();
// Close the streams.
cStream->Close();
mStream->Close();
// Return the encrypted buffer.
return ret;
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
return nullptr;
}
}
String^ DecryptTextFromMemory( array<Byte>^Data, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create a new MemoryStream using the passed
// array of encrypted data.
MemoryStream^ msDecrypt = gcnew MemoryStream( Data );
// Create a CryptoStream using the MemoryStream
// and the passed key and initialization vector (IV).
CryptoStream^ csDecrypt = gcnew CryptoStream( msDecrypt,(gcnew DESCryptoServiceProvider)->CreateDecryptor( Key, IV ),CryptoStreamMode::Read );
// Create buffer to hold the decrypted data.
array<Byte>^fromEncrypt = gcnew array<Byte>(Data->Length);
// Read the decrypted data out of the crypto stream
// and place it into the temporary buffer.
csDecrypt->Read( fromEncrypt, 0, fromEncrypt->Length );
//Convert the buffer into a string and return it.
return (gcnew ASCIIEncoding)->GetString( fromEncrypt );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
return nullptr;
}
}
int main()
{
try
{
// Create a new DESCryptoServiceProvider object
// to generate a key and initialization vector (IV).
DESCryptoServiceProvider^ DESalg = gcnew DESCryptoServiceProvider;
// Create a string to encrypt.
String^ sData = "Here is some data to encrypt.";
// Encrypt the string to an in-memory buffer.
array<Byte>^Data = EncryptTextToMemory( sData, DESalg->Key, DESalg->IV );
// Decrypt the buffer back to a string.
String^ Final = DecryptTextFromMemory( Data, DESalg->Key, DESalg->IV );
// Display the decrypted string to the console.
Console::WriteLine( Final );
}
catch ( Exception^ e )
{
Console::WriteLine( e->Message );
}
}
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;
class DESCSPSample
{
static void Main()
{
try
{
// Create a new DESCryptoServiceProvider object
// to generate a key and initialization vector (IV).
DESCryptoServiceProvider DESalg = new DESCryptoServiceProvider();
// Create a string to encrypt.
string sData = "Here is some data to encrypt.";
// Encrypt the string to an in-memory buffer.
byte[] Data = EncryptTextToMemory(sData, DESalg.Key, DESalg.IV);
// Decrypt the buffer back to a string.
string Final = DecryptTextFromMemory(Data, DESalg.Key, DESalg.IV);
// Display the decrypted string to the console.
Console.WriteLine(Final);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
public static byte[] EncryptTextToMemory(string Data, byte[] Key, byte[] IV)
{
try
{
// Create a MemoryStream.
MemoryStream mStream = new MemoryStream();
// Create a CryptoStream using the MemoryStream
// and the passed key and initialization vector (IV).
CryptoStream cStream = new CryptoStream(mStream,
new DESCryptoServiceProvider().CreateEncryptor(Key, IV),
CryptoStreamMode.Write);
// Convert the passed string to a byte array.
byte[] toEncrypt = new ASCIIEncoding().GetBytes(Data);
// Write the byte array to the crypto stream and flush it.
cStream.Write(toEncrypt, 0, toEncrypt.Length);
cStream.FlushFinalBlock();
// Get an array of bytes from the
// MemoryStream that holds the
// encrypted data.
byte[] ret = mStream.ToArray();
// Close the streams.
cStream.Close();
mStream.Close();
// Return the encrypted buffer.
return ret;
}
catch(CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
return null;
}
}
public static string DecryptTextFromMemory(byte[] Data, byte[] Key, byte[] IV)
{
try
{
// Create a new MemoryStream using the passed
// array of encrypted data.
MemoryStream msDecrypt = new MemoryStream(Data);
// Create a CryptoStream using the MemoryStream
// and the passed key and initialization vector (IV).
CryptoStream csDecrypt = new CryptoStream(msDecrypt,
new DESCryptoServiceProvider().CreateDecryptor(Key, IV),
CryptoStreamMode.Read);
// Create buffer to hold the decrypted data.
byte[] fromEncrypt = new byte[Data.Length];
// Read the decrypted data out of the crypto stream
// and place it into the temporary buffer.
csDecrypt.Read(fromEncrypt, 0, fromEncrypt.Length);
//Convert the buffer into a string and return it.
return new ASCIIEncoding().GetString(fromEncrypt);
}
catch(CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
return null;
}
}
}
Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
Module DESCSPSample
Sub Main()
Try
' Create a new DESCryptoServiceProvider object
' to generate a key and initialization vector (IV).
Dim DESalg As New DESCryptoServiceProvider
' Create a string to encrypt.
Dim sData As String = "Here is some data to encrypt."
' Encrypt the string to an in-memory buffer.
Dim Data As Byte() = EncryptTextToMemory(sData, DESalg.Key, DESalg.IV)
' Decrypt the buffer back to a string.
Dim Final As String = DecryptTextFromMemory(Data, DESalg.Key, DESalg.IV)
' Display the decrypted string to the console.
Console.WriteLine(Final)
Catch e As Exception
Console.WriteLine(e.Message)
End Try
End Sub
Function EncryptTextToMemory(ByVal Data As String, ByVal Key() As Byte, ByVal IV() As Byte) As Byte()
Try
' Create a MemoryStream.
Dim mStream As New MemoryStream
' Create a CryptoStream using the MemoryStream
' and the passed key and initialization vector (IV).
Dim cStream As New CryptoStream(mStream, _
New DESCryptoServiceProvider().CreateEncryptor(Key, IV), _
CryptoStreamMode.Write)
' Convert the passed string to a byte array.
Dim toEncrypt As Byte() = New ASCIIEncoding().GetBytes(Data)
' Write the byte array to the crypto stream and flush it.
cStream.Write(toEncrypt, 0, toEncrypt.Length)
cStream.FlushFinalBlock()
' Get an array of bytes from the
' MemoryStream that holds the
' encrypted data.
Dim ret As Byte() = mStream.ToArray()
' Close the streams.
cStream.Close()
mStream.Close()
' Return the encrypted buffer.
Return ret
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
Function DecryptTextFromMemory(ByVal Data() As Byte, ByVal Key() As Byte, ByVal IV() As Byte) As String
Try
' Create a new MemoryStream using the passed
' array of encrypted data.
Dim msDecrypt As New MemoryStream(Data)
' Create a CryptoStream using the MemoryStream
' and the passed key and initialization vector (IV).
Dim csDecrypt As New CryptoStream(msDecrypt, _
New DESCryptoServiceProvider().CreateDecryptor(Key, IV), _
CryptoStreamMode.Read)
' Create buffer to hold the decrypted data.
Dim fromEncrypt(Data.Length - 1) As Byte
' Read the decrypted data out of the crypto stream
' and place it into the temporary buffer.
csDecrypt.Read(fromEncrypt, 0, fromEncrypt.Length)
'Convert the buffer into a string and return it.
Return New ASCIIEncoding().GetString(fromEncrypt)
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
End Module
Poznámky
K dešifrování výsledku CreateDecryptor této metody použijte přetížení se stejnými parametry.