RIPEMD160Managed Construtor
Definição
Importante
Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.
Inicializa uma nova instância da classe RIPEMD160.
public:
RIPEMD160Managed();
public RIPEMD160Managed ();
Public Sub New ()
Exceções
A política não está em conformidade com o algoritmo FIPS.
Exemplos
O exemplo de código a seguir calcula o hash de RIPEMD160Managed classe para todos os arquivos em um diretório.
using namespace System;
using namespace System::IO;
using namespace System::Security::Cryptography;
// Print the byte array in a readable format.
void PrintByteArray( array<Byte>^array )
{
int i;
for ( i = 0; i < array->Length; i++ )
{
Console::Write( String::Format( "{0:X2}", array[ i ] ) );
if ( (i % 4) == 3 )
Console::Write( " " );
}
Console::WriteLine();
}
int main()
{
array<String^>^args = Environment::GetCommandLineArgs();
if ( args->Length < 2 )
{
Console::WriteLine( "Usage: hashdir <directory>" );
return 0;
}
try
{
// Create a DirectoryInfo object representing the specified directory.
DirectoryInfo^ dir = gcnew DirectoryInfo( args[ 1 ] );
// Get the FileInfo objects for every file in the directory.
array<FileInfo^>^files = dir->GetFiles();
// Initialize a RIPE160 hash object.
RIPEMD160 ^ myRIPEMD160 = RIPEMD160Managed::Create();
array<Byte>^hashValue;
// Compute and print the hash values for each file in directory.
System::Collections::IEnumerator^ myEnum = files->GetEnumerator();
while ( myEnum->MoveNext() )
{
FileInfo^ fInfo = safe_cast<FileInfo^>(myEnum->Current);
// Create a fileStream for the file.
FileStream^ fileStream = fInfo->Open( FileMode::Open );
// Compute the hash of the fileStream.
hashValue = myRIPEMD160->ComputeHash( fileStream );
// Write the name of the file to the Console.
Console::Write( "{0}: ", fInfo->Name );
// Write the hash value to the Console.
PrintByteArray( hashValue );
// Close the file.
fileStream->Close();
}
return 0;
}
catch ( DirectoryNotFoundException^ )
{
Console::WriteLine( "Error: The directory specified could not be found." );
}
catch ( IOException^ )
{
Console::WriteLine( "Error: A file in the directory could not be accessed." );
}
}
using System;
using System.IO;
using System.Security.Cryptography;
using System.Windows.Forms;
public class HashDirectory
{
[STAThreadAttribute]
public static void Main(String[] args)
{
string directory = "";
if (args.Length < 1)
{
FolderBrowserDialog fbd = new FolderBrowserDialog();
DialogResult dr = fbd.ShowDialog();
if (dr == DialogResult.OK)
{
directory = fbd.SelectedPath;
}
else
{
Console.WriteLine("No directory selected.");
return;
}
}
else
{
directory = args[0];
}
try
{
// Create a DirectoryInfo object representing the specified directory.
DirectoryInfo dir = new DirectoryInfo(directory);
// Get the FileInfo objects for every file in the directory.
FileInfo[] files = dir.GetFiles();
// Initialize a RIPE160 hash object.
RIPEMD160 myRIPEMD160 = RIPEMD160Managed.Create();
byte[] hashValue;
// Compute and print the hash values for each file in directory.
foreach (FileInfo fInfo in files)
{
// Create a fileStream for the file.
FileStream 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();
}
return;
}
catch (DirectoryNotFoundException)
{
Console.WriteLine("Error: The directory specified could not be found.");
}
catch (IOException)
{
Console.WriteLine("Error: A file in the directory could not be accessed.");
}
}
// Print the byte array in a readable format.
public static void PrintByteArray(byte[] array)
{
int i;
for (i = 0; i < array.Length; i++)
{
Console.Write(String.Format("{0:X2}", array[i]));
if ((i % 4) == 3) Console.Write(" ");
}
Console.WriteLine();
}
}
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
End Class
Comentários
O hash é usado como um valor exclusivo de tamanho fixo que representa uma grande quantidade de dados. Hashes de dois conjuntos de dados devem corresponder se e somente se os dados correspondentes também corresponderem. Pequenas alterações nos dados resultam em grandes alterações imprevisíveis no hash.
O tamanho do hash para o RIPEMD160 algoritmo é de 160 bits.