protected void Page_Load(object sender, EventArgs e)
    {
        string connectionString = "server=.;database=TYW;uid=sa;pwd=123.456;";// ConfigurationSettings.AppSettings["strCon"];
        SqlConnection mycon = new SqlConnection(connectionString);//创建数据库连接
        string sqlCategory = "select  * from Category";//查询商品分类表中信息
        string sqlPhoto = "select  * from productinfo";//查询商品表中信息
        SqlDataAdapter da = new SqlDataAdapter(sqlCategory, mycon);//创建数据适配器
        DataSet ds = new DataSet();//创建数据集
        try
        {
            //显式地打开数据库连接
            if (mycon.State.Equals(ConnectionState.Closed))
            {
                mycon.Open();
            }
            da.Fill(ds, "Category");//填充商品分类表
            da.SelectCommand.CommandText = sqlPhoto;
            da.Fill(ds, "productinfo");//填充商品信息表
        }
        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表示两个DataTable 对象之间的父/子关系。
        //   relationName:DataRelation 的名称。如果为 null 或空字符串 ("")，则当创建的对象添加到 System.Data.DataRelationCollection
        //     时，将指定一个默认名称。
        //   parentColumn:
        //     关系中的父级对应的列.
        //   childColumn:
        //     关系中的子级对应的列.
        DataRelation relat = new DataRelation("Category", ds.Tables["Category"].Columns["cateID"], ds.Tables["productinfo"].Columns["cateID"]);
        ds.Relations.Add(relat);//添加表间关系
        StringBuilder builder = new StringBuilder("");
        foreach (DataRow row in ds.Tables["Category"].Rows)
        {
            builder.Append("<b>");
            builder.Append(row["cateName"].ToString());
            builder.Append("</b><ul>");
            DataRow[] childRows = row.GetChildRows(relat);
            foreach (DataRow childRow in childRows)
            {
                builder.Append("<li>");
                builder.Append(childRow["productName"].ToString());
                builder.Append("</li>");
            }
            builder.Append("</ul>");
        }
        lbText.Text += builder.ToString();//将运行结果输出到页面中
    }

  1     protected void Page_Load(object sender, EventArgs e)
  2     {
  3         MakeMasterTable();  //创建主表
  4         MakeDetailTable();  //创建子表
  5         MakeDataRelation(); //建立主子表关联
  6     }
  7 
  8     private DataSet ds;
  9 
 10     private void MakeMasterTable()
 11     {
 12         //创建数据表对象
 13         DataTable table = new DataTable("MasterTable");
 14         DataColumn column;
 15         DataRow row;
 16         //创建数据列对象
 17         column = new DataColumn();
 18         //设置数据列的数据类型
 19         column.DataType = System.Type.GetType("System.Int32");
 20         column.ColumnName = "DictTypeID";//指定数据列名
 21         column.ReadOnly = true;          //设置数据列为只读列
 22         column.Unique = true;            //设置数据列中的值不允许重复
 23         table.Columns.Add(column);
 24 
 25         column = new DataColumn();
 26         column.DataType = System.Type.GetType("System.String");
 27         column.ColumnName = "DictTypeName";
 28         column.AutoIncrement = false;    //设置数据列中的值不自动递增
 29         column.Caption = "DictTypeName"; //设置数据列标题
 30         column.ReadOnly = false;
 31         column.Unique = false;
 32         table.Columns.Add(column);
 33         //创建列数组
 34         DataColumn[] PrimaryKeyColumns = new DataColumn[1];
 35         //将DictTypeID赋给列数组
 36         PrimaryKeyColumns[0] = table.Columns["DictTypeID"];
 37         table.PrimaryKey = PrimaryKeyColumns;//设置DictTypeID字段为主键
 38 
 39         ds = new DataSet();//创建数据集对象
 40         ds.Tables.Add(table);//将上面创建的数据表对象添加表数据集中
 41         //为数据表添加数据
 42         for (int i = 0; i< 2; i++)
 43         {
 44             row = table.NewRow();
 45             row["DictTypeID"] = i;
 46             row["DictTypeName"] = "DictTypeName " + i;
 47             table.Rows.Add(row);
 48         }
 49         GridView1.DataSource = ds;
 50         GridView1.DataBind();
 51     }
 52 
 53     private void MakeDetailTable()
 54     {
 55         DataTable table = new DataTable("DetailTable");
 56         DataColumn column;
 57         DataRow row;
 58 
 59         column = new DataColumn();
 60         column.DataType= System.Type.GetType("System.Int32");
 61         column.ColumnName = "DictItemID";
 62         column.AutoIncrement = true;//设置该数据列是自增列
 63         column.Caption = "DictItemID";
 64         column.ReadOnly = true;
 65         column.Unique = true;
 66 
 67         table.Columns.Add(column);
 68 
 69         column = new DataColumn();
 70         column.DataType= System.Type.GetType("System.String");
 71         column.ColumnName = "DictItemName";
 72         column.AutoIncrement = false;
 73         column.Caption = "DictItemName";
 74         column.ReadOnly = false;
 75         column.Unique = false;
 76         table.Columns.Add(column);
 77 
 78         column = new DataColumn();
 79         column.DataType= System.Type.GetType("System.Int32");
 80         column.ColumnName = "DictTypeID";
 81         column.AutoIncrement = false;
 82         column.Caption = "DictTypeID";
 83         column.ReadOnly = false;
 84         column.Unique = false;
 85         table.Columns.Add(column);
 86 
 87         ds.Tables.Add(table);
 88 
 89         for(int i = 0; i <= 4; i ++)
 90         {
 91             row = table.NewRow();
 92             //row["DictItemID"] = i;//因为该列是自增列所以不用赋值
 93             row["DictItemName"] = "DictItemName " + i;
 94             row["DictTypeID"] = 0;
 95             table.Rows.Add(row);
 96         }
 97         for(int i = 0; i <= 4; i ++)
 98         {
 99             row = table.NewRow();
100             //row["DictItemID"] = i + 5;
101             row["DictItemName"] = "DictItemName " + (i+5);
102             row["DictTypeID"] = 1;
103             table.Rows.Add(row);
104         }
105     }
106 
107     private void MakeDataRelation()
108     {
109         DataColumn masterColumn =
110             ds.Tables["MasterTable"].Columns["DictTypeID"];
111         DataColumn detailColumn =
112             ds.Tables["DetailTable"].Columns["DictTypeID"];
113         //使用DataRelation对象建立主子表的关联关系
114         DataRelation relation = new 
115             DataRelation("MasterDetail", masterColumn, detailColumn);
116         ds.Tables["DetailTable"].ParentRelations.Add(relation);
117     }