TreeViewコントロールツリーDemoはDataTableでTreeViewにバインド

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Data;



namespace TreeViewDemo

{

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

	{

		protected void Page_Load(object sender, EventArgs e)

		{

			if (!IsPostBack)

			{

				iniTree();

			}

		}



		private DataTable CreateData()

		{

			DataTable dt = new DataTable();

			dt.Columns.Add(new DataColumn("cName"));

			dt.Columns.Add(new DataColumn("cID"));

			dt.Columns.Add(new DataColumn("cPID"));



			for (int i = 0; i < 10; i++)

			{

				DataRow dr = dt.NewRow();

				dr["cName"] = "   " + i.ToString();

				dr["cID"] = i.ToString();

				dr["cPID"] = "";

				dt.Rows.Add(dr);



				for (int j = 0; j < 3; j++)

				{

					DataRow dr_sub = dt.NewRow();

					dr_sub["cName"] = "   " + j.ToString();

					dr_sub["cID"] = i.ToString() + "_" + j.ToString();

					dr_sub["cPID"] = i.ToString();

					dt.Rows.Add(dr_sub);

				}

			}



			return dt;

		}



		private void iniTree()

		{

			TreeView1.Nodes.Clear();



			DataTable dt = CreateData();

			TreeView1.Nodes.Add(new TreeNode("   ", ""));

			bindTree(dt, "", TreeView1.Nodes[0]);



			TreeView1.ImageSet = TreeViewImageSet.Arrows;

		}



		private void bindTree(DataTable dt, string pid, TreeNode ParentNode)

		{

			DataRow[] Rows = GetData(dt, pid);

			if (Rows.Length == 0) { return; }



			foreach (DataRow r in Rows)

			{

				TreeNode node = new TreeNode(r["cName"].ToString(),r["cID"].ToString());



				ParentNode.ChildNodes.Add(node);



				bindTree(dt, r["cID"].ToString(), node);

			}

		}



		private DataRow[] GetData(DataTable dt, string pid)

		{

			IEnumerable<DataRow> query = from r in dt.AsEnumerable()

						where r.Field<string>("cPID") == pid

						select r;

			return query.ToArray<DataRow>();

		}

	}

}