我有一个简单的DB管理器类(一个比它的能力更值得的名字)：

class DbManager

{

private MySqlConnectionStringBuilder _connectionString;

public DbManager()

{

_connectionString = new MySqlConnectionStringBuilder();

_connectionString.UserID = Properties.Database.Default.Username;

_connectionString.Password = Properties.Database.Default.Password;

_connectionString.Server = Properties.Database.Default.Server;

_connectionString.Database = Properties.Database.Default.Schema;

_connectionString.MaximumPoolSize = 5;

}

public MySqlConnection GetConnection()

{

MySqlConnection con = new MySqlConnection(_connectionString.GetConnectionString(true));

con.Open();

return con;

}

}

然后我在其他地方有另一个类来表示其中一个表中的记录,我填充它如下：

class Contact

{

private void Populate(object contactID)

{

using (OleDbConnection con = DbManager.GetConnection())

{

string q = "SELECT FirstName, LastName FROM Contacts WHERE ContactID = ?";

using (OleDbCommand cmd = new OleDbCommand(q, con))

{

cmd.Parameters.AddWithValue("?", contactID);

using (OleDbDataReader reader = cmd.ExecuteReader())

{

if (reader.HasRows)

{

reader.Read();

this.FirstName = reader.GetString(0);

this.LastName = reader.GetString(1);

this.Address = new Address();

this.Address.Populate(ContactID)

}

}

}

}

}

}

class Address

{

private void Populate(object contactID)

{

using (OleDbConnection con = DbManager.GetConnection())

{

string q = "SELECT Address1 FROM Addresses WHERE ContactID = ?";

using (OleDbCommand cmd = new OleDbCommand(q, con))

{

cmd.Parameters.AddWithValue("?", contactID);

using (OleDbDataReader reader = cmd.ExecuteReader())

{

if (reader.HasRows)

{

reader.Read();

this.Address1 = reader.GetString(0);

}

}

}

}

}

}

现在我认为所有using语句都会确保连接在完成后返回到池中,为下次使用做好准备,但是我有一个循环创建了数百个这样的联系人并填充它们,似乎连接没有被释放.

连接,命令和阅读器都在自己的使用语句中.