How to make openssl AES256 encryption in C#

  public static String decryptOpenSSL(String key,String data) throws IOException, GeneralSecurityException{
	   
	    OpenSSL opensll=new OpenSSL();
	    InputStream  is=OpenSSL.decrypt("AES256", key.getBytes(), new ByteArrayInputStream(data.getBytes()));
	    Base64 encode=new Base64();
	    
	     
	    BufferedReader in = new BufferedReader(new InputStreamReader(is));
	    String inputLine;
	   StringBuffer response = new StringBuffer();

	   while ((inputLine = in.readLine()) != null) {
	    response.append(inputLine);
	   }
	   in.close();
	      System.out.println(response);
	      //return encode.encode(response.toString().getBytes()).toString();
	      return response.toString();
	   }

public static String encryptOpenSSL(String key,String data) throws IOException, GeneralSecurityException{
	  
  	OpenSSL opensll=new OpenSSL();
  	InputStream  is=OpenSSL.encrypt("AES256", key.getBytes(), new ByteArrayInputStream(data.getBytes()), true);
  	BufferedReader in = new BufferedReader(new InputStreamReader(is));
  	String inputLine;
		StringBuffer response = new StringBuffer();

		while ((inputLine = in.readLine()) != null) {
			response.append(inputLine);
		}
		in.close();
     System.out.println(response);
     return response.toString();
  }