ASP.NET入门数据篇

对于网站编程的初学者来说，总是会上网找些源码来看，但久而久之还是停留在改代码的阶段，并不明白怎样去写一个完整的网站程序．有见如此我就开始写这样的文章（c#版），不足之处请批评指正．

数据库连接篇

在WEB项目里看到Web.config配置文件，在configuration这行加入下面代码用于和SQL服务器进行连接

<appSettings>
<!-- 数据库连接字符串 -->
<add key="ConnStr" value="Data Source=localhost;database=company;UID=sa;Password=;Persist Security Info=True;" />
</appSettings>

数据列表显示篇，如图：

using System;
using System.Data;
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;

//引用命名空间:SQL托管,配置文件
using System.Data.SqlClient;
using System.Configuration;

public partial class _Default : System.Web.UI.Page
{
    protected SqlConnection myconn = new SqlConnection(ConfigurationSettings.AppSettings["ConnectionString"]);
    //读取web.config配置文件中的数据库连接字符串,并连接到指定的数据库

protected void Page_Load(object sender, EventArgs e)
    {
        if(!IsPostBack)//判断页面是否第一次运行
     {

string strsql="select * from Product";//定义一个数据库的查询字符串
                DataSet ds = new DataSet();
                myconn.Open();//打开数据库连接
                SqlDataAdapter command = new SqlDataAdapter(strsql,myconn);//表示用于填充DataSet 和更新SQL Server 数据库的一组数据命令和一个数据库连接
                command.Fill(ds, "Product");
                productList.DataSource = ds.Tables[0].DefaultView;
                productList.DataBind();
                ds.Clear();
          myconn.Close();//关闭数据库连接
            }
 }

protected void grid_ItemDataBound(object sender, DataGridItemEventArgs e)
    {
        foreach (System.Web.UI.WebControls.HyperLink link in e.Item.Cells[7].Controls)
        {
            link.Attributes.Add("onClick", "if (!window.confirm('您真的要删除这条记录吗？')){return false;}");
        }
    }

}

数据添加篇

protected void btnAdd_Click(object sender, EventArgs e)
    {
        string ProductId = this.txtProductId.Text;
        string CategoryId = this.txtCategoryId.Text;
        string Name = this.txtName.Text;
        string Description = this.txtDescription.Text;
        string Price =this.txtPrice.Text;

string sql_Exeits = "select * from Product where ProductId='" + ProductId + "'";
        SqlCommand cmd_Exeits = new SqlCommand(sql_Exeits, myconn);
        myconn.Open();
        SqlDataReader rdr = cmd_Exeits.ExecuteReader();
        while (rdr.Read())
        {
            Response.Write("<script language='JavaScript'>");
            Response.Write("alert('对不起，该产品编号已经存在！')");
            Response.Write("</script>");
            this.txtCategoryId.Text = "";
            this.txtDescription.Text = "";
            this.txtName.Text = "";
            this.txtPrice.Text = "";
            this.txtProductId.Text = "";
            return;
        }
        rdr.Close();