SqlConnection //连接字符串
SqlCommand //执行sql命令的对象
DataReader //读取数据库中的记录
注意除了SqlConnection要记得关闭外 DataReader也要即使关闭,否则在下次使用未关闭的DataReader时候会出错。
示例代码如下:
- class Program
- {
- /// <summary>
- /// 应用程序的入口
- /// </summary>
- /// <param name="args"></param>
- /// <returns></returns>
- static void Main(string[] args)
- {
- string connectionString = GetConnectString();
- string queryString = "select * from person where id = 2";
- //string queryString = "delete from person where id = 2;";
- using (SqlConnection connection = new SqlConnection(connectionString))
- {
- SqlCommand command = connection.CreateCommand();
- command.CommandText = queryString;
- command.CommandType = CommandType.Text;
- try
- {
- connection.Open();
- //command.ExecuteNonQuery();//执行非查询命令
- SqlDataReader reader = command.ExecuteReader()//读取数据命令;
- while (reader.Read())
- {
- for (int i = 0; i < reader.FieldCount; i++)
- {
- Console.Write("{0}/t", reader[i]);
- }
- Console.WriteLine();
- }
- reader.Close();
- }
- catch (System.Exception ex)
- {
- Console.WriteLine(ex.Message);
- }
- }
- Console.Read();
- }
- #region 连接字符串
- /// <summary>
- /// 连接字符串
- /// </summary>
- /// <returns></returns>
- public static string GetConnectString()
- {
- return "Data Source=(local);Initial Catalog=mytestdb;"
- + "Integrated Security=SSPI";
- }
- #endregion