RC2CryptoServiceProvider.CreateDecryptor(Byte[], Byte[]) 方法
定义
public:
override System::Security::Cryptography::ICryptoTransform ^ CreateDecryptor(cli::array <System::Byte> ^ rgbKey, cli::array <System::Byte> ^ rgbIV);
public override System.Security.Cryptography.ICryptoTransform CreateDecryptor (byte[] rgbKey, byte[]? rgbIV);
public override System.Security.Cryptography.ICryptoTransform CreateDecryptor (byte[] rgbKey, byte[] rgbIV);
override this.CreateDecryptor : byte[] * byte[] -> System.Security.Cryptography.ICryptoTransform
Public Overrides Function CreateDecryptor (rgbKey As Byte(), rgbIV As Byte()) As ICryptoTransform
参数
- rgbKey
- Byte[]
用于对称算法的密钥。The secret key to use for the symmetric algorithm.
- rgbIV
- Byte[]
用于对称算法的初始化向量。The initialization vector to use for the symmetric algorithm.
返回
对称 RC2 解密器对象。A symmetric RC2 decryptor object.
例外
使用了 OFB 密码模式。An OFB cipher mode was used.
- 或 --or- 使用了反馈大小不是 8 位的 CFB 密码模式。A CFB cipher mode with a feedback size other than 8 bits was used.
- 或 --or- 使用了无效的密钥大小。An invalid key size was used.
或-or- 算法密钥大小不可用。The algorithm key size was not available.
示例
下面的代码示例对字符串进行加密和解密。The following code example encrypts and then decrypts a string.
using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;
namespace RC2CryptoServiceProvider_Examples
{
class MyMainClass
{
public static void Main()
{
// Create a new instance of the RC2CryptoServiceProvider class
// and automatically generate a Key and IV.
RC2CryptoServiceProvider rc2CSP = new RC2CryptoServiceProvider();
Console.WriteLine("Effective key size is {0} bits.", rc2CSP.EffectiveKeySize);
// Get the key and IV.
byte[] key = rc2CSP.Key;
byte[] IV = rc2CSP.IV;
// Get an encryptor.
ICryptoTransform encryptor = rc2CSP.CreateEncryptor(key, IV);
// Encrypt the data as an array of encrypted bytes in memory.
MemoryStream msEncrypt = new MemoryStream();
CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write);
// Convert the data to a byte array.
string original = "Here is some data to encrypt.";
byte[] toEncrypt = Encoding.ASCII.GetBytes(original);
// Write all data to the crypto stream and flush it.
csEncrypt.Write(toEncrypt, 0, toEncrypt.Length);
csEncrypt.FlushFinalBlock();
// Get the encrypted array of bytes.
byte[] encrypted = msEncrypt.ToArray();
///////////////////////////////////////////////////////
// This is where the data could be transmitted or saved.
///////////////////////////////////////////////////////
//Get a decryptor that uses the same key and IV as the encryptor.
ICryptoTransform decryptor = rc2CSP.CreateDecryptor(key, IV);
// Now decrypt the previously encrypted message using the decryptor
// obtained in the above step.
MemoryStream msDecrypt = new MemoryStream(encrypted);
CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read);
// Read the decrypted bytes from the decrypting stream
// and place them in a StringBuilder class.
StringBuilder roundtrip = new StringBuilder();
int b = 0;
do
{
b = csDecrypt.ReadByte();
if (b != -1)
{
roundtrip.Append((char)b);
}
} while (b != -1);
// Display the original data and the decrypted data.
Console.WriteLine("Original: {0}", original);
Console.WriteLine("Round Trip: {0}", roundtrip);
Console.ReadLine();
}
}
}
Imports System.IO
Imports System.Text
Imports System.Security.Cryptography
Module Crypto
Sub Main()
' Create a new instance of the RC2CryptoServiceProvider class
' and automatically generate a Key and IV.
Dim rc2CSP As New RC2CryptoServiceProvider()
Console.WriteLine("Effective key size is {0} bits.", rc2CSP.EffectiveKeySize)
' Get the key and IV.
Dim key As Byte() = rc2CSP.Key
Dim IV As Byte() = rc2CSP.IV
' Get an encryptor.
Dim encryptor As ICryptoTransform = rc2CSP.CreateEncryptor(key, IV)
' Encrypt the data as an array of encrypted bytes in memory.
Dim msEncrypt As New MemoryStream()
Dim csEncrypt As New CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write)
' Convert the data to a byte array.
Dim original As String = "Here is some data to encrypt."
Dim toEncrypt As Byte() = Encoding.ASCII.GetBytes(original)
' Write all data to the crypto stream and flush it.
csEncrypt.Write(toEncrypt, 0, toEncrypt.Length)
csEncrypt.FlushFinalBlock()
' Get the encrypted array of bytes.
Dim encrypted As Byte() = msEncrypt.ToArray()
'''''''''''''''''''''''''''''''''''''''''''''''''''''''
' This is where the data could be transmitted or saved.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''
'Get a decryptor that uses the same key and IV as the encryptor.
Dim decryptor As ICryptoTransform = rc2CSP.CreateDecryptor(key, IV)
' Now decrypt the previously encrypted message using the decryptor
' obtained in the above step.
Dim msDecrypt As New MemoryStream(encrypted)
Dim csDecrypt As New CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read)
' Read the decrypted bytes from the decrypting stream
' and place them in a StringBuilder class.
Dim roundtrip As New StringBuilder()
Dim b As Integer = 0
Do
b = csDecrypt.ReadByte()
If b <> -1 Then
roundtrip.Append(ChrW(b))
End If
Loop While b <> -1
' Display the original data and the decrypted data.
Console.WriteLine("Original: {0}", original)
Console.WriteLine("Round Trip: {0}", roundtrip)
Console.ReadLine()
End Sub
End Module
注解
此方法用于对使用具有相同参数的重载创建的加密消息进行解密 CreateEncryptor 。This method is used to decrypt an encrypted message created using the CreateEncryptor overload with the same parameters.