SymmetricAlgorithm.Key Property

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Gets or sets the secret key for the symmetric algorithm.

Namespace:  System.Security.Cryptography
Assembly:  mscorlib (in mscorlib.dll)


Public Overridable Property Key As Byte()
public virtual byte[] Key { get; set; }

Property Value

Type: array<System.Byte[]
The secret key to use for the symmetric algorithm.


Exception Condition

An attempt was made to set the key to nulla null reference (Nothing in Visual Basic).


The key size is invalid.


The secret key is used both for encryption and for decryption. For a symmetric algorithm to be successful, the secret key must be known only to the sender and the receiver. The valid key sizes are specified by the particular symmetric algorithm implementation and are listed in the LegalKeySizes property.

If this property is nulla null reference (Nothing in Visual Basic) when it is used, the GenerateKey method is called to create a new random value.

Version Information


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Windows Phone OS 7.0


For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.