本文实例讲述了asp.net实现DropDownList,TreeView,ListBox的无限极分类目录树。分享给大家供大家参考，具体如下：
#region DropDownList无限递归显示层次关系/// <summary>/// 创建无限分级下拉列表框/// </summary>/// <param name="ddlst">下拉控件</param>/// <param name="dt">源DataTable</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="parentid">深度字段 例如parentid</param>public static void CreateLevelDropDown(DropDownList ddlst, DataTable dt, string text, string value, string parentid){ ArrayList allItems = new ArrayList(); DataRow[] rows = dt.Select(parentid + "=0"); foreach (DataRow row in rows) CreateLevelDropDownAssistant(dt, ref allItems, row, string.Empty, text, value, parentid); ListItem[] items = new ListItem[allItems.Count]; allItems.CopyTo(items); ddlst.Items.AddRange(items);}/// <summary>/// 递归绑定子节点/// </summary>/// <param name="dt">源DataTable</param>/// <param name="items">数组</param>/// <param name="parentRow">当前节点</param>/// <param name="curHeader">前缀</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="parentid">深度字段 例如parentid</param>private static void CreateLevelDropDownAssistant(DataTable dt, ref ArrayList items, DataRow parentRow, string curHeader, string text, string value, string parentid){ ListItem newItem = new ListItem(curHeader + Until.CutString(parentRow[text].ToString(), 18, true), parentRow[value].ToString()); items.Add(newItem); DataRow[] rows = dt.Select(parentid + "=" + newItem.Value); for (int i = 0; i < rows.Length - 1; i++) CreateLevelDropDownAssistant(dt, ref items, rows[i], curHeader.Replace("┣", "┃").Replace("┗", "┣") + "┣", text, value, parentid); if (rows.Length > 0) CreateLevelDropDownAssistant(dt, ref items, rows[rows.Length - 1], curHeader.Replace("┣", "┃").Replace("┗", "┣") + "┗", text, value, parentid);}#endregion#region TreeView 无限递归显示层次关系目录树/// <summary>/// 创建无限分级目录树TreeView/// </summary>/// <param name="treeview">TreeView空间</param>/// <param name="dt">数据源DataTable</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="parentid">深度字段 例如parentid</param>public static void CreateLevelTreeView(TreeView treeview, DataTable dt, string text, string value, string parentid){ DataView dv = dt.DefaultView; dv.RowFilter = parentid + "=0"; foreach (DataRowView drv in dv) { TreeNode node = new TreeNode(); node.Text = drv[text].ToString(); node.Value = drv[value].ToString(); node.Expanded = false; treeview.Nodes.Add(node); CreatTreeViewChildNode(dv, node, text, value, parentid); }}/// <summary>/// 递归绑定子节点/// </summary>/// <param name="dv">源DataView</param>/// <param name="parentNode">当前节点</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="parentid">深度字段 例如parentid</param>private static void CreatTreeViewChildNode(DataView dv, TreeNode parentNode, string text, string value, string parentid){ dv.RowFilter = parentid + "=" + parentNode.Value; foreach (DataRowView row in dv) { TreeNode replyNode = new TreeNode(); replyNode.Text = row[text].ToString(); replyNode.Value = row[value].ToString(); replyNode.Expanded = false; parentNode.ChildNodes.Add(replyNode); CreatTreeViewChildNode(dv, replyNode, text, value, parentid); }}/// <summary>/// 创建无限分级目录树TreeView/// </summary>/// <param name="treeview">TreeView空间</param>/// <param name="dt">数据源DataTable</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="url">url字段</param>/// <param name="parentid">深度字段 例如parentid</param>public static void CreateLevelTreeView(TreeView treeview, DataTable dt, string text, string value, string url, string parentid){ DataView dv = dt.DefaultView; dv.RowFilter = parentid + "=0"; foreach (DataRowView drv in dv) { TreeNode node = new TreeNode(); node.Text = drv[text].ToString(); node.Value = drv[value].ToString(); node.NavigateUrl = drv[url].ToString(); node.Expanded = false; treeview.Nodes.Add(node); CreatTreeViewChildNode(dv, node, text, value, url, parentid); }}/// <summary>/// 递归绑定子节点/// </summary>/// <param name="dv">源DataView</param>/// <param name="parentNode">当前节点</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="url">url字段</param>/// <param name="parentid">深度字段 例如parentid</param>private static void CreatTreeViewChildNode(DataView dv, TreeNode parentNode, string text, string value, string url, string parentid){ dv.RowFilter = parentid + "=" + parentNode.Value; foreach (DataRowView row in dv) { TreeNode replyNode = new TreeNode(); replyNode.Text = row[text].ToString(); replyNode.Value = row[value].ToString(); replyNode.NavigateUrl = row[url].ToString(); replyNode.Expanded = false; parentNode.ChildNodes.Add(replyNode); CreatTreeViewChildNode(dv, replyNode, text, value, url, parentid); }}#endregion#region 创建无限分级ListBox/// <summary>/// 创建无限分级ListBox/// </summary>/// <param name="ddlst">ListBox控件</param>/// <param name="dt">源DataTable</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="parentid">深度字段 例如parentid</param>public static void CreateLevelListBox(ListBox ddlst, DataTable dt, string text, string value, string parentid){ ArrayList allItems = new ArrayList(); DataRow[] rows = dt.Select(parentid + "=0"); foreach (DataRow row in rows) CreateLevelListBoxAssistant(dt, ref allItems, row, string.Empty, text, value, parentid); ListItem[] items = new ListItem[allItems.Count]; allItems.CopyTo(items); ddlst.Items.AddRange(items);}/// <summary>/// 递归绑定子节点/// </summary>/// <param name="dt">源DataTable</param>/// <param name="items">数组</param>/// <param name="parentRow">当前节点</param>/// <param name="curHeader">前缀</param>/// <param name="text">text字段</param>/// <param name="value">value字段</param>/// <param name="parentid">深度字段 例如parentid</param>private static void CreateLevelListBoxAssistant(DataTable dt, ref ArrayList items, DataRow parentRow, string curHeader, string text, string value, string parentid){ ListItem newItem = new ListItem(curHeader + Until.CutString(parentRow[text].ToString(), 18, true), parentRow[value].ToString()); items.Add(newItem); DataRow[] rows = dt.Select(parentid + "=" + newItem.Value); for (int i = 0; i < rows.Length - 1; i++) CreateLevelListBoxAssistant(dt, ref items, rows[i], curHeader.Replace("┣", "┃").Replace("┗", "┣") + "┣", text, value, parentid); if (rows.Length > 0) CreateLevelListBoxAssistant(dt, ref items, rows[rows.Length - 1], curHeader.Replace("┣", "┃").Replace("┗", "┣") + "┗", text, value, parentid);}#endregion 
