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RIPEMD160 Class

Represents the abstract class from which all implementations of the MD160 hash algorithm inherit.

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

'Declaration
<ComVisibleAttribute(True)> _
Public MustInherit Class RIPEMD160 _
	Inherits HashAlgorithm

The RIPEMD160 type exposes the following members.

  NameDescription
Protected methodRIPEMD160Initializes a new instance of the RIPEMD160 class.
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  NameDescription
Public propertyCanReuseTransformGets a value indicating whether the current transform can be reused. (Inherited from HashAlgorithm.)
Public propertyCanTransformMultipleBlocksWhen overridden in a derived class, gets a value indicating whether multiple blocks can be transformed. (Inherited from HashAlgorithm.)
Public propertyHashGets the value of the computed hash code. (Inherited from HashAlgorithm.)
Public propertyHashSizeGets the size, in bits, of the computed hash code. (Inherited from HashAlgorithm.)
Public propertyInputBlockSizeWhen overridden in a derived class, gets the input block size. (Inherited from HashAlgorithm.)
Public propertyOutputBlockSizeWhen overridden in a derived class, gets the output block size. (Inherited from HashAlgorithm.)
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  NameDescription
Public methodClearReleases all resources used by the HashAlgorithm class. (Inherited from HashAlgorithm.)
Public methodComputeHash(Byte())Computes the hash value for the specified byte array. (Inherited from HashAlgorithm.)
Public methodComputeHash(Stream)Computes the hash value for the specified Stream object. (Inherited from HashAlgorithm.)
Public methodComputeHash(Byte(), Int32, Int32)Computes the hash value for the specified region of the specified byte array. (Inherited from HashAlgorithm.)
Public methodStatic memberCreateCreates an instance of the default implementation of the RIPEMD160 hash algorithm.
Public methodStatic memberCreate(String)Creates an instance of the specified implementation of the RIPEMD160 hash algorithm.
Public methodDisposeReleases all resources used by the current instance of the HashAlgorithm class. (Inherited from HashAlgorithm.)
Protected methodDispose(Boolean)Releases the unmanaged resources used by the HashAlgorithm and optionally releases the managed resources. (Inherited from HashAlgorithm.)
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodHashCoreWhen overridden in a derived class, routes data written to the object into the hash algorithm for computing the hash. (Inherited from HashAlgorithm.)
Protected methodHashFinalWhen overridden in a derived class, finalizes the hash computation after the last data is processed by the cryptographic stream object. (Inherited from HashAlgorithm.)
Public methodInitializeInitializes an implementation of the HashAlgorithm class. (Inherited from HashAlgorithm.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
Public methodTransformBlockComputes 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. (Inherited from HashAlgorithm.)
Public methodTransformFinalBlockComputes the hash value for the specified region of the specified byte array. (Inherited from HashAlgorithm.)
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  NameDescription
Protected fieldHashSizeValueRepresents the size, in bits, of the computed hash code. (Inherited from HashAlgorithm.)
Protected fieldHashValueRepresents the value of the computed hash code. (Inherited from HashAlgorithm.)
Protected fieldStateRepresents the state of the hash computation. (Inherited from HashAlgorithm.)
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Hash functions map binary strings of an arbitrary length to small binary strings of a fixed length. A cryptographic hash function has the property that it is computationally infeasible to find two distinct inputs that hash to the same value; that is, 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.

RIPEMD-160 is a 160-bit cryptographic hash function. It is intended for use as a replacement for the 128-bit hash functions MD4, MD5, and RIPEMD. RIPEMD was developed in the framework of the EU project RIPE (RACE Integrity Primitives Evaluation, 1988-1992).

NoteNote

RIPEMD160 has been superseded by the Secure Hash Algorithms SHA-256 and SHA-512 and their derived classes. SHA256 and SHA512 offer better security and performance than RIPEMD160. Use RIPEMD160 only for compatibility with legacy applications and data.

The following code example calculates the RIPEMD160 hash for all files in a directory.

Imports System
Imports System.IO
Imports System.Security.Cryptography
Imports System.Windows.Forms

Public Class HashDirectory

    Public Shared Sub Main(ByVal args() As String)
        Dim directory As String 
        If args.Length < 1 Then 
            Dim fdb As New FolderBrowserDialog
            Dim dr As DialogResult = fdb.ShowDialog()
            If (dr = DialogResult.OK) Then
                directory = fdb.SelectedPath
            Else
                Console.WriteLine("No directory selected")
                Return 
            End If 
        Else
            directory = args(0)
        End If 
        Try 
            ' Create a DirectoryInfo object representing the specified directory. 
            Dim dir As New DirectoryInfo(directory)
            ' Get the FileInfo objects for every file in the directory. 
            Dim files As FileInfo() = dir.GetFiles()
            ' Initialize a RIPE160 hash object. 
            Dim myRIPEMD160 As RIPEMD160 = RIPEMD160Managed.Create()
            Dim hashValue() As Byte 
            ' Compute and print the hash values for each file in directory. 
            Dim fInfo As FileInfo
            For Each fInfo In files
                ' Create a fileStream for the file. 
                Dim fileStream As FileStream = fInfo.Open(FileMode.Open)
                ' Be sure it's positioned to the beginning of the stream.
                fileStream.Position = 0
                ' Compute the hash of the fileStream.
                hashValue = myRIPEMD160.ComputeHash(fileStream)
                ' Write the name of the file to the Console.
                Console.Write(fInfo.Name + ": ")
                ' Write the hash value to the Console.
                PrintByteArray(hashValue)
                ' Close the file.
                fileStream.Close()
            Next fInfo
            Return 
        Catch DExc As DirectoryNotFoundException
            Console.WriteLine("Error: The directory specified could not be found.")
        Catch IOExc As IOException
            Console.WriteLine("Error: A file in the directory could not be accessed.")
        End Try 

    End Sub 

    ' Print the byte array in a readable format. 
    Public Shared Sub PrintByteArray(ByVal array() As Byte)
        Dim i As Integer 
        For i = 0 To array.Length - 1
            Console.Write(String.Format("{0:X2}", array(i)))
            If i Mod 4 = 3 Then
                Console.Write(" ")
            End If 
        Next i
        Console.WriteLine()

    End Sub 'PrintByteArray
End Class

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

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