RSACryptoServiceProvider.Decrypt 方法

定義

命名空間:

System.Security.Cryptography

組件:

System.Security.Cryptography.dll

解密先前加密的資料。

多載

Decrypt(Byte[], Boolean)	以 RSA 演算法解密資料。
Decrypt(Byte[], RSAEncryptionPadding)	解密先前使用指定填補以 RSA 演算法加密的資料。

Decrypt(Byte[], Boolean)

來源:

RSACryptoServiceProvider.Unix.cs

以 RSA 演算法解密資料。

public:
 cli::array <System::Byte> ^ Decrypt(cli::array <System::Byte> ^ rgb, bool fOAEP);

public byte[] Decrypt (byte[] rgb, bool fOAEP);

override this.Decrypt : byte[] * bool -> byte[]

Public Function Decrypt (rgb As Byte(), fOAEP As Boolean) As Byte()

參數

rgb

Byte[]

要解密的資料。

fOAEP

Boolean

true 使用 OAEP 填補執行直接的 RSA 解密，false 則使用 PKCS#1 v1.5 填補。

傳回

Byte[]

解密的資料，亦即加密前的原始純文字。

例外狀況

CryptographicException

無法取得密碼編譯服務提供者 (CSP)。

-或-

fOAEP 參數為 true，而且 rgb 參數的長度大於 KeySize。

-或-

金鑰與加密的資料不相符。 不過，例外狀況文字可能不正確。 例如，它可能指出 Not enough storage is available to process this command。

ArgumentNullException

rgb 為 null。

範例

下列程式代碼範例會加密和解密數據。

這個範例會 ASCIIEncoding 使用 類別;不過， UnicodeEncoding 類別在大型數據作業中可能比較好。 加密的值可以儲存為 nvarchar Microsoft SQL Server 中的數據類型。

using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
int main()
{
   try
   {
      
      //Create a UnicodeEncoder to convert between byte array and string.
      ASCIIEncoding^ ByteConverter = gcnew ASCIIEncoding;
      String^ dataString = "Data to Encrypt";
      
      //Create byte arrays to hold original, encrypted, and decrypted data.
      array<Byte>^dataToEncrypt = ByteConverter->GetBytes( dataString );
      array<Byte>^encryptedData;
      array<Byte>^decryptedData;
      
      //Create a new instance of the RSACryptoServiceProvider class 
      // and automatically create a new key-pair.
      RSACryptoServiceProvider^ RSAalg = gcnew RSACryptoServiceProvider;
      
      //Display the origianl data to the console.
      Console::WriteLine( "Original Data: {0}", dataString );
      
      //Encrypt the byte array and specify no OAEP padding.  
      //OAEP padding is only available on Microsoft Windows XP or
      //later.  
      encryptedData = RSAalg->Encrypt( dataToEncrypt, false );
      
      //Display the encrypted data to the console. 
      Console::WriteLine( "Encrypted Data: {0}", ByteConverter->GetString( encryptedData ) );
      
      //Pass the data to ENCRYPT and boolean flag specifying 
      //no OAEP padding.
      decryptedData = RSAalg->Decrypt( encryptedData, false );
      
      //Display the decrypted plaintext to the console. 
      Console::WriteLine( "Decrypted plaintext: {0}", ByteConverter->GetString( decryptedData ) );
   }
   catch ( CryptographicException^ e ) 
   {
      
      //Catch this exception in case the encryption did
      //not succeed.
      Console::WriteLine( e->Message );
   }

}

using System;
using System.Security.Cryptography;
using System.Text;

class RSACSPSample
{
    static void Main()
    {
        try
        {
            //Create a UnicodeEncoder to convert between byte array and string.
            ASCIIEncoding ByteConverter = new ASCIIEncoding();

            string dataString = "Data to Encrypt";

            //Create byte arrays to hold original, encrypted, and decrypted data.
            byte[] dataToEncrypt = ByteConverter.GetBytes(dataString);
            byte[] encryptedData;
            byte[] decryptedData;

            //Create a new instance of the RSACryptoServiceProvider class
            // and automatically create a new key-pair.
            RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider();

            //Display the origianl data to the console.
            Console.WriteLine("Original Data: {0}", dataString);

            //Encrypt the byte array and specify no OAEP padding.
            //OAEP padding is only available on Microsoft Windows XP or
            //later.
            encryptedData = RSAalg.Encrypt(dataToEncrypt, false);

            //Display the encrypted data to the console.
            Console.WriteLine("Encrypted Data: {0}", ByteConverter.GetString(encryptedData));

            //Pass the data to ENCRYPT and boolean flag specifying
            //no OAEP padding.
            decryptedData = RSAalg.Decrypt(encryptedData, false);

            //Display the decrypted plaintext to the console.
            Console.WriteLine("Decrypted plaintext: {0}", ByteConverter.GetString(decryptedData));
        }
        catch(CryptographicException e)
        {
            //Catch this exception in case the encryption did
            //not succeed.
            Console.WriteLine(e.Message);
        }
    }
}

Imports System.Security.Cryptography
Imports System.Text

Module RSACSPExample

    Sub Main()
        Try
            'Create a UnicodeEncoder to convert between byte array and string.
            Dim ByteConverter As New ASCIIEncoding

            Dim dataString As String = "Data to Encrypt"

            'Create byte arrays to hold original, encrypted, and decrypted data.
            Dim dataToEncrypt As Byte() = ByteConverter.GetBytes(dataString)
            Dim encryptedData() As Byte
            Dim decryptedData() As Byte

            'Create a new instance of the RSACryptoServiceProvider class 
            ' and automatically create a new key-pair.
            Dim RSAalg As New RSACryptoServiceProvider

            'Display the origianl data to the console.
            Console.WriteLine("Original Data: {0}", dataString)

            'Encrypt the byte array and specify no OAEP padding.  
            'OAEP padding is only available on Microsoft Windows XP or
            'later.  
            encryptedData = RSAalg.Encrypt(dataToEncrypt, False)

            'Display the encrypted data to the console. 
            Console.WriteLine("Encrypted Data: {0}", ByteConverter.GetString(encryptedData))

            'Pass the data to ENCRYPT and boolean flag specifying 
            'no OAEP padding.
            decryptedData = RSAalg.Decrypt(encryptedData, False)

            'Display the decrypted plaintext to the console. 
            Console.WriteLine("Decrypted plaintext: {0}", ByteConverter.GetString(decryptedData))
        Catch e As CryptographicException
            'Catch this exception in case the encryption did
            'not succeed.
            Console.WriteLine(e.Message)
        End Try
    End Sub 

End Module

備註

使用 Encrypt 來加密數據以使用此方法進行解密。

另請參閱

• Decrypt(Byte[], RSAEncryptionPadding)
• 密碼編譯服務

Decrypt(Byte[], RSAEncryptionPadding)

來源:

RSACryptoServiceProvider.Unix.cs

解密先前使用指定填補以 RSA 演算法加密的資料。

public:
 override cli::array <System::Byte> ^ Decrypt(cli::array <System::Byte> ^ data, System::Security::Cryptography::RSAEncryptionPadding ^ padding);

public override byte[] Decrypt (byte[] data, System.Security.Cryptography.RSAEncryptionPadding padding);

override this.Decrypt : byte[] * System.Security.Cryptography.RSAEncryptionPadding -> byte[]

Public Overrides Function Decrypt (data As Byte(), padding As RSAEncryptionPadding) As Byte()

參數

data

Byte[]

要解密的資料。

padding

RSAEncryptionPadding

填補。

傳回

Byte[]

已解密的資料。

例外狀況

ArgumentNullException

data 為 null。

-或-

padding 為 null。

CryptographicException

不支援填補模式。

備註

padding 必須是 RSAEncryptionPadding.Pkcs1 或 RSAEncryptionPadding.OaepSHA1。