请问一下：
最近我使用了using 自动关闭机制来关闭数据库的连接。但在调试的时候发现，using只能关闭通过new来实例化的连接[如:SqlConnection conn = new SqlConnection(strConn)],但是却不能自动关闭通过类名来访问的静态SqlConnection连接[如:DBHelper.conn]。
请问一下，这是为什么啊？

请问有人知道吗？

DBHelper.cs
        private static string StrConn = ConfigurationManager.ConnectionStrings["SQLConn"].ConnectionString;
        public static SqlConnection conn = new SqlConnection(StrConn);
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AddFormDAL.cs
        //封装
        public void PrepareSQLCommand(string sql,SqlConnection conn,SqlCommand comm)
        {
            if (conn.State == ConnectionState.Closed)
            {
                conn.Open();
            }
             = sql;
            comm.Connection = conn;
        }

        //增删改
        public int ExecuteNonQuery(string str)
        {
            int count = 0;
            using (SqlCommand comm = new SqlCommand())
            {
                PrepareSQLCommand(str, DBHelper.conn, comm);
                count = comm.ExecuteNonQuery();
            }
            return count;
        }

??

谢谢你们的回复，六楼说的，跟我了解到得是一样的~~~~~~~~~~