//**************************************************
//* Private
//**************************************************
//-------------------------------------------------
/// <summary>
/// Find hash algorithm that corresponds to the
/// requested method
/// </summary>
/// <exception cref="NotSupportedException">Thrown
/// when requested method is not recognized.</exception>
private static HashAlgorithm CreateHashAlgorithm(ChecksumMethod method)
{
switch (method)
{
case ChecksumMethod.SHA1: return(new SHA1CryptoServiceProvider());
case ChecksumMethod.MD5: return(new MD5CryptoServiceProvider());
case ChecksumMethod.CRC32: return(new CRC32());
default: throw new NotSupportedException(string.Concat("Requested checksum method ", method, " is not supported"));
}
}
//**************************************************
//* Public interface
//**************************************************
//-------------------------------------------------
/// <summary>
/// Compute checksum for the specified source file,
/// return it as hex string ("F3BA87...").
/// </summary>
/// <remarks>
/// This method will be run on a worker thread
/// (from thread pool) via async invocation.
/// </remarks>
public static string ComputeChecksum(string sourceFile, ChecksumMethod method, Action <decimal> progressNotifier)
{
System.Threading.Thread.Sleep(100);
using (var hashAlgorithm = CreateHashAlgorithm(method))
using (var source = new TrackingStream(File.OpenRead(sourceFile), progressNotifier))
{
var hash = hashAlgorithm.ComputeHash(source);
var msg = new StringBuilder(128);
foreach (var byteValue in hash)
{
msg.AppendFormat(byteValue.ToString("X2", CultureInfo.InvariantCulture));
}
return(msg.ToString());
}
}
protected ENetChecksum(ChecksumMethod method)
{
Method = method;
}