CryptographicEngine.Decrypt(CryptographicKey, IBuffer, IBuffer) 方法

定義

命名空間:

Windows.Security.Cryptography.Core

使用對稱或非對稱演算法解密先前加密的內容。

public:
 static IBuffer ^ Decrypt(CryptographicKey ^ key, IBuffer ^ data, IBuffer ^ iv);

 static IBuffer Decrypt(CryptographicKey const& key, IBuffer const& data, IBuffer const& iv);

public static IBuffer Decrypt(CryptographicKey key, IBuffer data, IBuffer iv);

function decrypt(key, data, iv)

Public Shared Function Decrypt (key As CryptographicKey, data As IBuffer, iv As IBuffer) As IBuffer

參數

key

CryptographicKey

用於解密的密碼編譯金鑰。 這可以是非對稱或對稱金鑰。 如需詳細資訊，請參閱 AsymmetricKeyAlgorithmProvider 和 SymmetricKeyAlgorithmProvider。

data

IBuffer

包含加密資料的緩衝區。

iv

IBuffer

包含初始化向量的緩衝區。 如果初始化向量 (IV) 用來加密資料，您必須使用相同的 IV 來解密資料。 如需詳細資訊，請參閱 加密。

傳回

IBuffer

解密的資料。

範例

public void SampleCipherDecryption(
    String strAlgName,
    IBuffer buffEncrypt,
    IBuffer iv,
    BinaryStringEncoding encoding,
    CryptographicKey key)
{
    // Declare a buffer to contain the decrypted data.
    IBuffer buffDecrypted;

    // Open an symmetric algorithm provider for the specified algorithm. 
    SymmetricKeyAlgorithmProvider objAlg = SymmetricKeyAlgorithmProvider.OpenAlgorithm(strAlgName);

    // The input key must be securely shared between the sender of the encrypted message
    // and the recipient. The initialization vector must also be shared but does not
    // need to be shared in a secure manner. If the sender encodes a message string 
    // to a buffer, the binary encoding method must also be shared with the recipient.
    buffDecrypted = CryptographicEngine.Decrypt(key, buffEncrypt, iv);

    // Convert the decrypted buffer to a string (for display). If the sender created the
    // original message buffer from a string, the sender must tell the recipient what 
    // BinaryStringEncoding value was used. Here, BinaryStringEncoding.Utf8 is used to
    // convert the message to a buffer before encryption and to convert the decrypted
    // buffer back to the original plaintext.
    String strDecrypted = CryptographicBuffer.ConvertBinaryToString(encoding, buffDecrypted);
}

備註

key參數可以是使用PersistedKeyProvider類別從憑證取得的保存金鑰。

如果金鑰是保存的金鑰，而且解密作業需要 UI 或花費很長的時間，請改用 DecryptAsync 方法。 例如，使用強式保護的金鑰解密時，需要 UI。 在使用保存金鑰且預期 UI 的情況下，請使用 DecryptAsync 方法，因為 Decrypt 方法將會失敗。

另請參閱

• AsymmetricKeyAlgorithmProvider
• Encrypt(CryptographicKey, IBuffer, IBuffer)
• SymmetricKeyAlgorithmProvider
• 密碼編譯金鑰