SqlConnection sqlConn=new SqlConnection("server=.;database=pubs;
user id=sa;password=;");
SqlCommand sqlComm=new SqlCommand("select * from authors",sqlConn);
//操作在打开和断开数据库之间
sqlConn.Open();
SqlDataReader dr=sqlComm.ExcuteReader();
while(dr.Read())
{
for  (int i=0; i<dr.FieldCount; i++) 
{
Console.Write(dr.GetValue(i).ToString()+" ");
}
Console.WriteLine();
}
dr.Close();
sqlConn.Close();

SqlConnection sqlConn=new SqlConnection("server=.;
database=pubs;user id=sa;password=;");
SqlDataAdapter adapter=new SqlDataAdapter("select * from authors",sqlConn);
//用来自动生产更新命令
SqlCommandBuilder cb=new SqlCommandBuilder(adapter);
sqlConn.Open();
DataSet ds=new DataSet();
adapter.Fill(ds);
sqlConn.Close();
//处理数据在打开和关闭之后
for (int i=0; i<ds.Tables[0].Rows.Count; i++)
{
for (int j=0; j<ds.Tables[0].Columns.Count; j++
{
Console.Write(ds.Tables[0].Rows[i][j]+" ");
}
Console.WriteLine();
}
//更改数据
ds.Tables[0].Rows[0][1]="A";
ds.Tables[0].Rows[1].Delete();
//更新数据库
sqlConn.Open();
adapter.Update(ds);
sqlConn.Close();