HashAlgorithm Class

[This documentation is for preview only, and is subject to change in later releases. Blank topics are included as placeholders.]

Represents the base class from which all implementations of cryptographic hash algorithms must derive.

Inheritance Hierarchy

System. . :: . .Object
  Microsoft.SPOT.Cryptoki. . :: . .SessionContainer
    System.Security.Cryptography..::..HashAlgorithm
      System.Security.Cryptography. . :: . .KeyedHashAlgorithm

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

Syntax

'Declaration
Public Class HashAlgorithm _
    Inherits SessionContainer _
    Implements ICryptoTransform, IDisposable

public class HashAlgorithm : SessionContainer, 
    ICryptoTransform, IDisposable

public ref class HashAlgorithm : public SessionContainer, 
    ICryptoTransform, IDisposable

type HashAlgorithm =  
    class
        inherit SessionContainer
        interface ICryptoTransform
        interface IDisposable
    end

public class HashAlgorithm extends SessionContainer implements ICryptoTransform, IDisposable

The HashAlgorithm type exposes the following members.

Constructors

	Name	Description
	HashAlgorithm(HashAlgorithmType, Session)	Initializes a new instance of the HashAlgorithm class with the specified algorithm and session context.
	HashAlgorithm(HashAlgorithmType, String)	Initializes a new instance of the HashAlgorithm class with the specified algorithm and service provider.

Top

Properties

	Name	Description
	CanReuseTransform	Gets a value indicating whether the current transform can be reused.
	CanTransformMultipleBlocks	When overridden in a derived class, gets a value indicating whether multiple blocks can be transformed.
	Hash	Gets the value of the computed hash code.
	HashSize	Gets the size, in bits, of the computed hash code.
	HashType	Gets the hash algorithm type.
	InputBlockSize	When overridden in a derived class, gets the input block size.
	IsDisposed	(Inherited from SessionContainer.)
	OutputBlockSize	When overridden in a derived class, gets the output block size.
	Session	(Inherited from SessionContainer.)

Top

Methods

	Name	Description
	Clear	Releases all resources used by the HashAlgorithm class.
	ComputeHash(array<Byte> [] () [] [])	Computes the hash value for the specified byte array.
	ComputeHash(Stream)	Computes the hash value for the specified Stream object.
	ComputeHash(array<Byte> [] () [] [], Int32, Int32)	Computes the hash value for the specified region of the specified byte array.
	Dispose() () () ()	(Inherited from SessionContainer.)
	Dispose(Boolean)	Releases the unmanaged resources used by the HashAlgorithm and optionally releases the managed resources. (Overrides SessionContainer. . :: . .Dispose(Boolean).)
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	(Inherited from SessionContainer.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	Initialize	Initializes an implementation of the HashAlgorithm class.
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)
	TransformBlock	Computes the hash value for the specified region of the input byte array and copies the specified region of the input byte array to the specified region of the output byte array.
	TransformFinalBlock	Computes the hash value for the specified region of the specified byte array.

Top

Fields

	Name	Description
	HashValue	Represents the value of the computed hash code.
	m_digest	Contains the digest.
	m_hashSize	Contains the hash size.
	m_isDisposed	(Inherited from SessionContainer.)
	m_isSessionClosing	(Inherited from SessionContainer.)
	m_mechanism	Contains the mechanism.
	m_ownsSession	(Inherited from SessionContainer.)
	m_session	(Inherited from SessionContainer.)
	State	Represents the state of the hash computation.

Top

Remarks

Hash functions are fundamental to modern cryptography. These functions map binary strings of an arbitrary length to small binary strings of a fixed length, known as hash values. A cryptographic hash function has the property that it is computationally infeasible to find two distinct inputs that hash to the same value. Hash functions are commonly used with digital signatures and for data integrity.

The hash is used as a unique value of fixed size representing a large amount of data. Hashes of two sets of data should match if the corresponding data also matches. Small changes to the data result in large unpredictable changes in the hash.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

See Also

Reference

System.Security.Cryptography Namespace