%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

html xmlns="http://www.w3.org/1999/xhtml">
head runat="server">
    title>无标题页/title>
/head>
body>
    form id="form1" runat="server">
    div>

    /div>
    asp:Label ID="lbText" runat="server">/asp:Label>
    /form>
/body>
/html>

using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

using System.Data.SqlClient;
using System.Text;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string connectionString = ConfigurationSettings.AppSettings["strCon"];
        SqlConnection mycon = new SqlConnection(connectionString);//创建数据库连接
        string sqlCategory = "select ID,C_Name from Photo_Category";//查询相册分类表中信息
        string sqlPhoto = "select CategoryID,Title from Photo";//查询相册表中信息
        SqlDataAdapter da = new SqlDataAdapter(sqlCategory, mycon);//创建数据适配器
        DataSet ds = new DataSet();//创建数据集
        try
        {
            if (mycon.State.Equals(ConnectionState.Closed))
            { mycon.Open(); }//显式地打开数据库连接
            da.Fill(ds, "Photo_Category");//填充相册分类表
            da.SelectCommand.CommandText = sqlPhoto;
            da.Fill(ds, "Photo");//填充相册信息表
        }
        finally
        {
            mycon.Close();//显式地关闭数据库连接
        }
        //创建DataRelation对象，关联表间关系
        DataRelation relat = new DataRelation("Photo_Category",  ds.Tables["Photo_Category"].Columns["ID"],ds.Tables["Photo"].Columns["CategoryID"]);
        ds.Relations.Add(relat);//添加表间关系
        StringBuilder builder = new StringBuilder("");
        foreach (DataRow row in ds.Tables["Photo_Category"].Rows)
        {
            builder.Append("b>");
            builder.Append(row["C_Name"].ToString());
            builder.Append("/b>ul>");
            DataRow[] childRows = row.GetChildRows(relat);
            foreach (DataRow childRow in childRows)
            {
                builder.Append("li>");
                builder.Append(childRow["Title"].ToString());
                builder.Append("/li>");
            }
            builder.Append("/ul>");
        }
        lbText.Text += builder.ToString();//将运行结果输出到页面中
    }

}