Question

Is this good enough ? do I need to add anything or remove anything ? like a rollback to my Sql Queries ? add catch() ? should my function accept only the property that I need or the object it self ? and how can I let the presentation layer know that the function’s code was executed with no errors .. should I make it book instead of void or what ?

    public static void DeleteAllCabinFeaturesFromACruise(int CruiseID)
    {
        string commandText = "DELETE FROM Cruise_Features WHERE CruiseID = @cruiseId";
        SqlConnection connection = new SqlConnection(ConnectionString);
        SqlCommand command = new SqlCommand(commandText, connection);

        try
        {
            using (connection)
            {
                using (command)
                {
                    command.Parameters.AddWithValue("@cruiseId", CruiseID);
                    connection.Open();
                    command.ExecuteScalar();
                }
            }
        }

        finally { connection.Close(); }
    }

Answer 1

You are not using using correctly. The idea of using is to wrap some resource, that needs to be released in a safety-west, that protects it from exceptions. So, the correct way of using using (ha-ha) is the following:

using(SqlConnection connection = new SqlConnection(ConnectionString)){
{
    using(SqlCommand command = new SqlCommand(commandText, connection)){
        //your code here
    }
}

The second issue is that you are executing your query as if it should return Scalar value. It’s OK, but I think it’s better use just Execute: command.Execute(); And, if you want some error handling, you’d better wrap

connection.Open();
command.ExecuteScalar();

in a try ... catch block like you have. Like this:

//I would place it inside inner-most using block, but nothing wrong placing it outside
try{
    connection.open();
    command.Parameters.AddWithValue("@cruiseId", CruiseID);
     command.Execute();
}
//this catches ALL exceptions, regardless of source. Better narrow this down with
//some specific exception, like SQLException or something like that
catch (Exception e){
    return false; //or whatever you need to do
}