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HMACSHA1 Constructor (array<Byte[])

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Initializes a new instance of the HMACSHA1 class with the specified key data.

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

Syntax

'Declaration
Public Sub New ( _
    key As Byte() _
)

public HMACSHA1(
    byte[] key
)

Parameters

  • key
    Type: array<System.Byte[]
    The secret key for HMACSHA1 encryption. The key can be any length, but if it is more than 64 bytes long it will be hashed (using SHA-1) to derive a 64-byte key. Therefore, the recommended size of the secret key is 64 bytes.

Exceptions

Exception Condition
ArgumentNullException

The key parameter is nulla null reference (Nothing in Visual Basic).

Remarks

HMACSHA1 is a type of keyed hash algorithm that is constructed from the SHA1 hash function and used as an HMAC, or hash-based message authentication code. The HMAC process mixes a secret key with the message data, hashes the result with the hash function, mixes that hash value with the secret key again, then applies the hash function a second time. The output hash will be 160 bits (20 bytes) in length.

Version Information

Silverlight

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

Platforms

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