c# - 正确使用与 C# 和 MySQL 的连接

Question

C#/MySQL 交互的典型示例涉及如下代码(为简单起见，我跳过了 try/catches 和错误检查):

conn = new MySqlConnection(cs);
conn.Open();
string stm = "SELECT * FROM Authors";
MySqlCommand cmd = new MySqlCommand(stm, conn);
rdr = cmd.ExecuteReader();

该方案是一个用于独立应用程序和 WCF Web 服务的类库。那么，我是否应该在每次查询时都打开一个连接？还是应该在打开程序的时候打开一次？

Answer 1

要扩展 HackedByChinese 的建议，请考虑以下内容。您有一个主要的协调方法来处理连接的创建、打开、设置事务，然后调用执行不同类型工作(查询)的辅助方法。

  public static void UpdateMyObject(string connection, object myobject)
        {
        try
        {
            using (SqlConnection con = new SqlConnection(connection))
            {
                con.Open();
                using (SqlTransaction trans = con.BeginTransaction())
                {
                    WorkingMethod1(con, myobject);
                    WorkingMethod2(con, myobject);
                    WorkingMethod3(con, myobject);
                    trans.Commit();
                }
                con.Close();
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show("SOMETHING BAD HAPPENED!!!!!!!  {0}", ex.Message);
        }
    }

    private static void WorkingMethod1(SqlConnection con, object myobject)
    {
        // Do something here against the database
    }

    private static void WorkingMethod2(SqlConnection con, object myobject)
    {
        // Do something here against the database
    }

    private static void WorkingMethod3(SqlConnection con, object myobject)
    {
        // Do something here against the database
    }