对一段SQL进行语法检查

下面的C#代码用来检查一段SQL语句的语法是否正确：

    public string CheckSQLCommand(string connectionString, string sql)
    {
        String message = null;

        try
        {
            using (SqlConnection sqlConnection = new SqlConnection(connectionString))
            {
                sqlConnection.Open();
                SqlCommand sqlCommand = sqlConnection.CreateCommand();
                sqlCommand.CommandTimeout = 1;
                sqlCommand.CommandText = "SET PARSEONLY ON;" + sql + ";SET PARSEONLY OFF;";
                sqlCommand.ExecuteNonQuery();
            }
        }
        catch (Exception ex)
        {
            if (ex.Message.IndexOf("Timeout") == -1)
            {
                SqlException sqlException = ex as SqlException;
                if (sqlException != null)
                {
                    if (sqlException.Number < 50000 && sqlException.Number != 2627)
                    {
                        message = ex.Message;
                    }
                }
            }
        }

        return message;
    }