C# SQLite，读取后数据库被锁定

Question

看了一些相关的帖子，不是很明白。发生的事情是，在访问数据库之后，数据库被锁定，因此可以读取，但不能写入。退出应用程序后，数据库再次解锁。你能不能看着它像我无知一样和我说话，指出我处理这个问题的错误？

 public static Partner GetOnePartner(string code)
 {
    Partner partner = new Partner();
    SQLiteConnection connection = GroomwatchDB.GetConnection();
    string sqlStatement = "SELECT * FROM partners WHERE partner_code = @partner_code";

    SQLiteCommand command = new SQLiteCommand(sqlStatement, connection);
    command.Parameters.Add(new SQLiteParameter("@partner_code"));
    command.Parameters["@partner_code"].Value = code;

    try
    {
        connection.Open();
        SQLiteDataReader reader = command.ExecuteReader(CommandBehavior.SingleRow);
        if(reader.Read())
        {
            partner.Code = reader["partner_code"].ToString();
            partner.Last_name = reader["last_name"].ToString();
            partner.First_name = reader["first_name"].ToString();
            partner.Pay_rate = (double)reader["pay_rate"];
            partner.Active = reader["active"].ToString();
        }
        else
        {
            partner.Code = code;
            partner.Last_name = "Not Found";
        }

    }
    catch (SQLiteException ex)
    {
       throw ex;
    }
    finally
    {
        connection.Close();
    }

    return partner;

}

Answer 1

您应该使用 IDisposable 模式正确使用您的连接。

事实上，每个实现了IDisposable接口的类都需要调用using。这确保方法 Dispose() 被调用，因此非托管资源被清除（并且您不会以打开的文件结束）：

public static Partner GetOnePartner(string code)
 {
    Partner partner = new Partner();
    string sqlStatement = "SELECT * FROM partners WHERE partner_code = @partner_code";
    using(SQLiteConnection connection = GroomwatchDB.GetConnection())
    using(SQLiteCommand command = new SQLiteCommand(sqlStatement, connection))
    {
        command.Parameters.Add(new SQLiteParameter("@partner_code"));
        command.Parameters["@partner_code"].Value = code;
        connection.Open();
        using(SQLiteDataReader reader = command.ExecuteReader(CommandBehavior.SingleRow))
        {
            if(reader.Read())
            {
                partner.Code = reader["partner_code"].ToString();
                partner.Last_name = reader["last_name"].ToString();
                partner.First_name = reader["first_name"].ToString();
                partner.Pay_rate = (double)reader["pay_rate"];
                partner.Active = reader["active"].ToString();
            }
            else
            {
                partner.Code = code;
                partner.Last_name = "Not Found";
            }
        }
    }
    return partner;
}

参考文献：

Proper use of the IDisposable interface
Do I have to Dispose the SQLiteCommand objects?
SqlConnection SqlCommand SqlDataReader IDisposable

C# SQLite，读取后数据库被锁定

C# SQLite, database being left locked after a read

c#

sqlite

locked