C#数据库操作的几种读值对比

11程序的编写总能体现其灵活性,或许编程的乐趣莫不如此,而往往大都的初学者应用起又总显得不很灵活,究其因,感性认识到理性认识需要有个过程,而其中一个最简单的方法就是我们都要学会比较,这样或许我们能发现很多让我们感兴趣的问题:

下面就传递来的ID值,我们根据此ID然后从数据库中获得我们想要的东西,我列举了几种方法,共享给所有的初学者,如果对你有帮助,幸甚倍至!!!!!

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.Data.SqlClient;

public partial class edit : System.Web.UI.Page

{

     protected void Page_Load(object sender, EventArgs e)

     {

         if (!IsPostBack)

         {

             int tid = Convert.ToInt32(Request.QueryString["id"]);

             if (tid != null)

             {

                //从类中取得数据库的连接

                 Class1 cl = new Class1();

                 SqlConnection conn = cl.sqlc();

                 //以下为数据库连接

                 //string connstring = ConfigurationManager.ConnectionStrings["TreeConn"].ConnectionString;

                 //SqlConnection conn = new SqlConnection(connstring);

                 //conn.Open();

                 //以下是利用ExecuteScalar()方法:

                 SqlCommand comm = new SqlCommand("select ColunmnName from t_Column where ColumnId=" + tid + "", conn);

                 Label1.Text = comm.ExecuteScalar().ToString();

　　　　　　　　

                 //以下为dataset方法

                 DataSet ds = new DataSet();

                SqlDataAdapter sda = new SqlDataAdapter("select ColunmnName from t_Column where ColumnId=" + tid + "", conn);

                 sda.Fill(ds, "name");

                 Label1.Text = ds.Tables["name"].Rows[0]["ColunmnName"].ToString();

                // 以下是利用ExecuteReader()方法:

               SqlCommand comm = new SqlCommand("select ColunmnName from t_Column where ColumnId=" + tid + "", conn);

                 SqlDataReader sdr=comm.ExecuteReader();

                 if (sdr.Read())

                 {

                     Label1.Text = sdr["ColunmnName"].ToString();

                     Label2.Text = sdr["ColunmnName"].ToString();

                 }

             }

            // Button del = new Button();

             //del = (Button)Page.FindControl("Button1");

            // del.Attributes.Add("onclick", "return confirm('确定修改吗？');");

         }

     }

}