数据获取的两种方法：DataList和SqlDataReader

string strsql = "Data Source=Thomas-PC;Initial Catalog=Book;Integrated Security=True";
SqlConnection conn = new SqlConnection(strsql);
try{
Label1.Text = "数据库链接成功";
conn.Open();
string sqlQuery = "select * from users";
SqlCommand cmd = new SqlCommand(sqlQuery,conn);
SqlDataReader sqr = cmd.ExecuteReader();  //DataReader向后读写的类，不够灵活
while (sqr.Read())
Response.Write(sqr["author"]+"<br/>");
/*SqlDataAdapter sda = new SqlDataAdapter(sqlQuery,conn);
DataSet ds = new DataSet();           //DataSet数据集会消耗一些额外的内存，灵活性高
int numbers = sda.Fill(ds,"Tables");
for(int i = 0; i < numbers; i++)
Response.Write(ds.Tables["Tables"].Rows[i]["id"].ToString()+"<br/>");
string deleteQuery = "delete from users where id = 1";
SqlCommand sqlcommand = new SqlCommand(deleteQuery,conn);
sqlcommand.ExecuteNonQuery();
*/
Label1.Text = "数据删除成功";
}
catch (Exception ee){
Label1.Text = ee.ToString();
}