下面是一个Treeview动态的绑定3层深度的树的代码，有需要的朋友可以参考一下

代码如下:

using System;
using System.Collections;
using System.Configuration;
using System.Data;
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.Data.SqlClient;
using Common;
using DataAccess;

public partial class Controls_ProductType2 : System.Web.UI.UserControl
{

  ProductType productType = new ProductType();
  Product product = new Product();

 protected void TreeView_TreeNodePopulate(object sender, TreeNodeEventArgs e)
  {

    if (e.Node.ChildNodes.Count == 0)
    {
      switch (e.Node.Depth)
      {
        case 0:
          PopulateCategories(e.Node);
          break;
        case 1:
          PopulateProductType(e.Node);
          break;
        case 2:
          PopulateProducts(e.Node);
          break;
      }
    }

   //  int i = TreeToXml.TreeToXML(TreeView1, "D:/TreeToXML.xml");

  }

  protected void Page_Load(object sender, EventArgs e)
  {

  }

  //第一级节点（parentID=0）
  void PopulateCategories(TreeNode node)
  {
    DataTable dt = new DataTable();
    dt = productType.GetListByFatherNode();

    if (dt.Rows.Count > 0)
    {
      foreach (DataRow row in dt.Rows)
      {
        TreeNode NewNode = new TreeNode(row["ProductTypeName"].ToString(), row["ProductTypeID"].ToString(),"","../WebProductList.aspx?productTypeIdOne="+ row["ProductTypeID"].ToString() +"","");
        NewNode.PopulateOnDemand = true;
        NewNode.SelectAction = TreeNodeSelectAction.Expand;
        node.ChildNodes.Add(NewNode);
        node.Expanded = true ;
      }
    }

  }

  //第二级节点
  void PopulateProductType(TreeNode node)
  {
    DataTable dt = new DataTable();
    QueryParam queryparam = new QueryParam();
    queryparam.Add("ParentID", QueryParam.RELATION.EQ, "" + node.Value + "");
    dt = productType.GetListByBranchNode(queryparam);
    unity3d http://www.unitymanual.com/

创新互联专注于海晏网站建设服务及定制，我们拥有丰富的企业做网站经验。 热诚为您提供海晏营销型网站建设，海晏网站制作、海晏网页设计、海晏网站官网定制、微信小程序定制开发服务，打造海晏网络公司原创品牌,更为您提供海晏网站排名全网营销落地服务。

    if (dt.Rows.Count > 0)
    {
      foreach (DataRow row in dt.Rows)
      {
        TreeNode NewNode = new TreeNode(row["ProductTypeName"].ToString(), row["ProductTypeID"].ToString(), "", "../WebProductList.aspx?productTypeIdTwo=" + row["ProductTypeID"].ToString() + "", "");
        NewNode.PopulateOnDemand = true;
        NewNode.SelectAction = TreeNodeSelectAction.Expand;
        node.ChildNodes.Add(NewNode);
        node.Expanded = false ;
      }
    }
  }

  //第三个节点
  void PopulateProducts(TreeNode node)
  {
    DataTable dt = new DataTable();
    QueryParam queryparam = new QueryParam();
    queryparam.Add("ProductTypeItemID", QueryParam.RELATION.EQ, "" + node.Value + "");
    dt = product.GetList(queryparam);

    if (dt.Rows.Count > 0)
    {
      foreach (DataRow row in dt.Rows)
      {
        TreeNode NewNode = new TreeNode(row["ProductName"].ToString(), row["ProductID"].ToString(), "", "../WebProductDetaile.aspx?productID=" + row["ProductID"].ToString() + "", "");
        //NewNode.PopulateOnDemand = false;
        //NewNode.SelectAction = TreeNodeSelectAction.None;
        NewNode.PopulateOnDemand =true ;
        NewNode.SelectAction = TreeNodeSelectAction.Expand ;
        node.ChildNodes.Add(NewNode);
        node.Expanded = false;
      }
    }
  }

}

另外有需要云服务器可以了解下创新互联scvps.cn，海内外云服务器15元起步，三天无理由+7*72小时售后在线，公司持有idc许可证，提供“云服务器、裸金属服务器、高防服务器、香港服务器、美国服务器、虚拟主机、免备案服务器”等云主机租用服务以及企业上云的综合解决方案，具有“安全稳定、简单易用、服务可用性高、性价比高”等特点与优势，专为企业上云打造定制，能够满足用户丰富、多元化的应用场景需求。

文章标题：关于ASP.NET中TreeView用法的一个小例子-创新互联
浏览地址：http://scyanting.com/article/dchieo.html