Подправить функцию main, так, чтобы вместо директории можно было передавать путь к файлу

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 SHA256 hash object.
      SHA256 ^ mySHA256 = SHA256Managed::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 = mySHA256->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." );
   }
 
}

#include "stdafx.h"
 
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
   {
 
      // Initialize a SHA256 hash object.
      SHA256 ^ mySHA256 = SHA256Managed::Create();
      array<Byte>^hashValue;
 
         FileStream^ fileStream = gcnew FileStream( args[ 1 ] ,FileMode::Open);
         // Compute the hash of the fileStream.
         hashValue = mySHA256->ComputeHash( fileStream );
 
         // Write the name of the file to the Console.
         Console::Write( "{0}: ", args[ 1 ] );
 
         // 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." );
   }
}

#include "stdafx.h"
using namespace System;
using namespace System::IO;
using namespace System::Security::Cryptography;
 
void PrintByteArray(array<Byte>^ array) {
    for (int 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<System::String ^> ^args) {
    if (args->Length < 1) {
        Console::WriteLine("Filename missing.");
        return 1;
    }
 
    SHA256^ mySHA256 = SHA256Managed::Create();
    {
        try {
            FileStream^ fileStream = gcnew FileStream(
                args[0],
                FileMode::Open);
            array<Byte>^ hashValue = mySHA256->ComputeHash(fileStream);
            PrintByteArray(hashValue);
            fileStream->Close();
        }
        catch (FileNotFoundException^ ex) {
            Console::WriteLine("File not found");
            return 1;
        }
    }
    return 0;
}