无限级分类的增删改

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

public partial class SuperAdmin_ClassManage : System.Web.UI.Page
{
    public DataTable dt;
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            GetData();
            BindParent();
        }
    }

    /**//// <summary>
    /// 获取数据，填充datatable
    /// </summary>
    public void GetData()
    {
        sc.BLL.NewsClass ncbll = new sc.BLL.NewsClass();
        DataSet mydata = ncbll.getDataSet("*", "", "ncid desc");
        this.dt = mydata.Tables[0];
    }

    /**//// <summary>
    /// 绑定父节点
    /// </summary>
    public void BindParent()
    {
        if (dt.Rows.Count > 0)
        {
            foreach (DataRow dr in dt.Rows)
            {
                if (dr["ParentID"].ToString().Trim() == "0")
                {
                    this.dropClassType.Items.Add(new ListItem(dr["NCName"].ToString(), dr["NCID"].ToString()));
                    this.BindChild(this.dropClassType, dt, dr["NCID"].ToString(), 1);
                }
            }
        }
        this.dropClassType.Items.Insert(0, new ListItem("根目录", "0"));
    }

    /**//// <summary>
    /// 绑定子节点
    /// </summary>
    /// <param name="drop"></param>
    /// <param name="d"></param>
    /// <param name="id"></param>
    /// <param name="?"></param>
    public void BindChild(DropDownList drop, DataTable d, string id, int len)
    {
        DataRow[] dr = d.Select("ParentID = '" + id + "'", "NCID desc");
        for (int i = 0; i < dr.Length; i++)
        {
            this.dropClassType.Items.Add(new ListItem(this.Sanpce(len) + dr[i]["NCName"].ToString(), dr[i]["NCID"].ToString()));
            this.BindChild(drop, d, dr[i]["NCID"].ToString(), len + 1);
        }
    }

    /**//// <summary>
    /// 根据长度来判断缩进
    /// </summary>
    /// <param name="len"></param>
    /// <returns></returns>
    public string Sanpce(int len)
    {
        string str = "";
        for (int j = 0; j < len; j++)
        {
            str += "　";
        }
        return str;
    }

    /**//// <summary>
    /// 修改栏目
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected void btnUpdate_Click(object sender, EventArgs e)
    {
        if (this.dropClassType.SelectedValue != "0")
        {
            int id = int.Parse(this.dropClassType.SelectedValue.ToString());
            sc.BLL.NewsClass ncbll = new sc.BLL.NewsClass();
            sc.Model.NewsClass ncmodel = new sc.Model.NewsClass();
            ncmodel.ParentID = ncbll.GetModel(id).ParentID;
            ncmodel.NCID = id;
            ncmodel.NCName = this.txrClassName.Text.ToString().Trim();
            bool r = ncbll.Update(ncmodel);
            if (r)
            {
                Page.ClientScript.RegisterStartupScript(this.GetType(), "s", "<script>alert('修改成功！');location.reload('classmanage.aspx')</script>");
            }
            else
            {
                Page.ClientScript.RegisterStartupScript(this.GetType(), "fail", "<script>alert('修改失败，请您稍后再试！');</script>");
            }
        }
        else
        {
            Page.ClientScript.RegisterStartupScript(this.GetType(), "fail", "<script>alert('不能编辑“根目录”，请您选择真实的栏目。');</script>");
        }
    }

    /**//// <summary>
    /// 添加新的目录
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected void btnInsert_Click(object sender, EventArgs e)
    {
        if (this.txtNewClass.Text != "")
        {
            sc.BLL.NewsClass bll = new sc.BLL.NewsClass();
            sc.Model.NewsClass model = new sc.Model.NewsClass();
            model.ParentID = int.Parse(this.dropClassType.SelectedValue.ToString());
            model.NCName = this.txtNewClass.Text.ToString();
            int r = bll.Add(model);
            if (r > 0)
            {
                Page.ClientScript.RegisterStartupScript(this.GetType(), "s", "<script>alert('添加成功！');location.reload('classmanage.aspx')</script>");
            }
            else
            {
                Page.ClientScript.RegisterStartupScript(this.GetType(), "fail", "<script>alert('添加失败，请您稍后再试！');</script>");
            }
        }
        else
        {
            Page.ClientScript.RegisterStartupScript(this.GetType(), "fail", "<script>alert('栏目名称不能为空！');</script>");
        }
    }

    /**//// <summary>
    /// 删除当前选中项
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected void btnDel_Click(object sender, EventArgs e)
    {
        int id = int.Parse(this.dropClassType.SelectedValue.ToString());
        sc.BLL.NewsClass bll = new sc.BLL.NewsClass();
        DataSet mydata = bll.getDataSet("*", "parentid='" + id + "'", "");
        if (id == 0)
        {
            Page.ClientScript.RegisterStartupScript(this.GetType(), "fail", "<script>alert('不能删除“根目录”，请您重新选择');</script>");

        }
        else if (mydata.Tables[0].Rows.Count > 0)
        {
            Page.ClientScript.RegisterStartupScript(this.GetType(), "fail", "<script>alert('必须将其子节点全部删除后才能删除父节点');</script>");
        }
        else
        {
            bool r = bll.Delete(id);
            if (r)
            {
                Page.ClientScript.RegisterStartupScript(this.GetType(), "s", "<script>alert('删除成功！');location.reload('classmanage.aspx')</script>");
            }
            else
            {
                Page.ClientScript.RegisterStartupScript(this.GetType(), "fail", "<script>alert('删除子节点时，必须保证其版块的新闻数量为0，否则不能删除！');</script>");
            }
        }

    }
}

数据库

USE [zhuxue]
GO
/**//****** 对象:  Table [dbo].[NewsClass]    脚本日期: 11/05/2007 16:57:32 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[NewsClass](
    [NCID] [int] IDENTITY(1,1) NOT NULL,
    [NCName] [nvarchar](20) COLLATE Chinese_PRC_CI_AS NULL,
    [ParentID] [int] NULL,
    [RootID] [int] NOT NULL CONSTRAINT [DF_NewsClass_RootID]  DEFAULT ((0)),
 CONSTRAINT [PK_NewsClass] PRIMARY KEY CLUSTERED 
(
    [NCID] ASC
)WITH (PAD_INDEX  = OFF, IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]