ADO.NET三个核心对象的简要说明
SqlConnection //连接字符串
SqlCommand //执行sql命令的对象
SqlDataReader //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:
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
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();
}
/// <summary>
/// 连接字符串
/// </summary>
/// <returns></returns>
public static string GetConnectString()
{
return "Data Source=(local);Init ial Catalog=mytestdb;"
+ "Integrated Security=SSPI";
}
希望天一直是蓝的,真的很美......