本文演示了如何在C#中连接Oracle数据库。

string sqlSql = "SELECT * FROM　A";
        //从配置文件中获取连接字符串信息
        OracleConnection conn = new OracleConnection(ConfigurationManager.ConnectionStrings["connStr"].ConnectionString);
        //数据库读取对象
        OracleDataReader reader = null;

            try
            {
            //打开数据库连接
            conn.Open();
            OracleCommand comd = new OracleCommand(sqlSql, conn);
            if (!string.IsNullOrEmpty("FIELD_A"))
            {
                sqlSql += string.Format(" AND FIELD_A =:FIELD_A");
                //通过AddWithValue方法将参数设置到SQL语句中
                comd.Parameters.AddWithValue("FIELD_A", "ABC");
            }
            comd.CommandText = sqlSql;
            reader = comd.ExecuteReader();
            while (reader.Read())
            {
            	A.abc=reader.GetString(0);
            }
            
            catch (Exception e)
            {
                throw e;
            }
            finally
            {
                if (conn.State == ConnectionState.Open)
                    // 关闭连接
                    conn.Close();
            }
        }