树的操作（绑定数据库，添加新节点，删除节点）(加实现)

前台：

<% @ Master Language = " C# "  AutoEventWireup = " true "  CodeFile = " MasterPage.master.cs "  Inherits = " Master_MasterPage "   %>

<! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >

< html  xmlns ="http://www.w3.org/1999/xhtml"   >
< head  runat ="server" >
     < title ></ title >
     < link  href ="../App_Themes/myTheme/Basic.css"  rel ="stylesheet"  type ="text/css"   />
</ head >
< body  style ="margin:0" >
     < form  id ="form1"  runat ="server" >
     < div >
     < table  style ="width:100%;height:100%;border-collapse:collapse;border-color:#44a938"  border ="1" "" >
     < tr >< td  style ="height:50px; font-size:15px"  colspan ="2"  align ="center" > God is a girl! </ td ></ tr >
        
             < tr >
                 < td  style ="width: 160px"  valign ="top" >
                  < asp:TreeView  ID ="TreeLeft"  runat ="server"  ShowLines ="True"  OnSelectedNodeChanged ="TreeLeft_SelectedNodeChanged"   >
                     </ asp:TreeView >
                    Parent: < asp:DropDownList  ID ="ddlParentID"  runat ="server"  Width ="90px" ></ asp:DropDownList >< br  />
                    Text: &nbsp;   < asp:TextBox  ID ="txtNodeName"  runat ="server"  Width ="85px" ></ asp:TextBox >< br  />
                     < asp:Button  ID ="btnSubmit"  runat ="server"  Text ="Submit"  OnClick ="btnSubmit_Click"   />
                     < asp:Button  ID ="btnDelete"  runat ="server"  Text ="Delete"  OnClick ="btnDelete_Click"   />
                 </ td >
                 < td  valign ="top"   >
                     < asp:ContentPlaceHolder  ID ="ContentPlaceHolder1"  runat ="server" >
                     </ asp:ContentPlaceHolder >
                 </ td >
             </ tr >

        </ table >
     </ div >
     </ form >
</ body >
</ html >

后台：

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;
using  System.Data.SqlClient;

public  partial  class  Master_MasterPage : System.Web.UI.MasterPage
{
   
     protected   void  Page_Load( object  sender, EventArgs e)
    {
         if  ( ! IsPostBack)
        {
            TreeleftBind();
            bindGroup();
        }
    }
     #region  绑定树
     private   void  TreeleftBind()
    {
         this .TreeLeft.Nodes.Clear();
        DataTable dt  =  master.Getdt();
        DataView dv  =   new  DataView(dt);
        dv.RowFilter  =   " TreeParentID = 0 " ;
        TreeNode node  =   new  TreeNode();
         foreach  (DataRowView drv  in  dv)
        {
            node.Text  =  drv[ " TreeName " ].ToString();
            node.Value  =  drv[ " ID " ].ToString();
            node.Expanded  =   true ;
             this .TreeLeft.Nodes.Add(node);
            AddReplies(dt, node);
        }
    }
     private   void  AddReplies(DataTable dt, TreeNode node)
    {

        DataView dv  =   new  DataView(dt);
        
        dv.RowFilter  =   " TreeParentID=' "   +  node.Value  +   " ' " ;
         foreach  (DataRowView row  in  dv)
        {
            TreeNode replyNode  =   new  TreeNode();
            replyNode.Text  =  row[ " TreeName " ].ToString();
            replyNode.Value  =  row[ " ID " ].ToString();
            replyNode.NavigateUrl  =  row[ " Link " ].ToString();
            replyNode.Expanded  =   false ;
            node.ChildNodes.Add(replyNode);
            replyNode.ShowCheckBox  =   true ;
            
            AddReplies(dt, replyNode);
        }

    }
     #endregion

     #region  绑定DropDownList
     private   void  bindGroup()
    {
         this .ddlParentID.Items.Clear();
        DataTable dt  =  master.Getdt();  // 获取所有节点
         if  (dt.Rows.Count  >   0 )
        {
             foreach  (DataRow row  in  dt.Rows)
            {
                 if  (row[ " TreeParentID " ].ToString().Trim()  ==   " 0 " ) // 绑定根节点
                {
                     this .ddlParentID.Items.Add( new  ListItem(row[ " TreeName " ].ToString(), row[ " Id " ].ToString()));
                     this .bindDropChildItem( this .ddlParentID, dt, row[ " ID " ].ToString(),  1 );
                }
            }
        }
    }
     private   void  bindDropChildItem(DropDownList d, DataTable dt,  string  id,  int  length)
    {
        DataRow[] rows  =  dt.Select( " TreeParentID=' "   +  id  +   " ' " ,  " Id ASC " ); // 取出id子节点进行绑定
         for  ( int  i  =   0 ; i  <  rows.Length; i ++ )
        {
             this .ddlParentID.Items.Add( new  ListItem( this .SpaceLength(length)  +  rows[i][ " TreeName " ].ToString(), rows[i][ " Id " ].ToString()));
             this .bindDropChildItem(d, dt, rows[i][ " Id " ].ToString(), length  +   1 ); // 空白数目加1
        }
    }
     private   string  SpaceLength( int  i)
    {
         string  space  =   "" ;
         for  ( int  j  =   0 ; j  <  i; j ++ )
        {
            space  +=   " -- " ;
        }
         return  space;
    }
     #endregion

     #region  动态增加节点
     protected   void  btnSubmit_Click( object  sender, EventArgs e)
    {
         string  rootID  =  ddlParentID.SelectedValue.ToString();
         string  txtName  =   this .txtNodeName.Text;
        master.InsertNode( " AutoTree " ,  " TreeName " ,  " TreeParentID " ,txtName,rootID);
         this .txtNodeName.Text  =   "" ;
        TreeleftBind();
        bindGroup();
    }
     #endregion

     #region  动态删除节点
     protected   void  btnDelete_Click( object  sender, EventArgs e)
    {
         if  (TreeChecked()  !=   0 )
        {
             string  strjavascript  =   " <script language='javascript'>alert('You cant delete the node which have childnode!')</script> " ;
            Page.ClientScript.RegisterStartupScript( this .GetType(),  " onclick " , strjavascript);
        }
         else
        {
             foreach  (TreeNode node  in  TreeLeft.CheckedNodes)
            {

                 string  SelectTreeID  =  node.Value;
                master.DeleteRecords(SelectTreeID);
            }
            TreeleftBind();
            bindGroup();
        }
    }
     protected   int  TreeChecked()
    {
         int  count  =   0 ;
         foreach  (TreeNode node  in   this .TreeLeft.CheckedNodes)
        {
             if  (node.ChildNodes.Count  >   0 )
            {
                count  =  count  +   1 ;
            }
        }
         return  count;
    }
     #endregion

     #region  页面跳转
     protected   void  TreeLeft_SelectedNodeChanged( object  sender, EventArgs e)
    {
        TreeNode node  =  TreeLeft.SelectedNode;
         if  (node.ChildNodes.Count  !=   0 )
        {
            node.SelectAction  =  TreeNodeSelectAction.Expand;
            node.Expanded  =   true ;
        }
         else
        {
             string  url  =   " @ "   +  node.NavigateUrl;
            Response.Redirect(url); // 数据库中LINK字段的数据为：~/WOW/Moniqi.aspx
             // Response.Redirect(@"~/Yule/wowmoni.aspx");
            
        }
    }
     #endregion
}

类：

using  System;
using  System.Data;
using  System.Configuration;
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;
using  System.Data.SqlClient;

///   <summary>
///  Summary description for master
///   </summary>
public   class  master
{
    
     public  master()
    {
         //
         //  TODO: Add constructor logic here
         //
    }

     ///   <summary>
     ///  删除节点
     ///   </summary>
     ///   <param name="datakey"></param>
     public   static   void  DeleteRecords( string  datakey)
    {
         string  strDelete  =  String.Format( " DELETE FROM [AutoTree] where ID = {0} " , datakey);
        GetDB.cmdExecute(strDelete);
    }

     ///   <summary>
     ///  返回DataTable
     ///   </summary>
     ///   <returns></returns>
     public   static  DataTable Getdt()
    {
        SqlConnection cn  =  GetDB.GetConnect();
         string  strSQL  =   " select * from AutoTree " ;
        SqlDataAdapter da  =   new  SqlDataAdapter(strSQL, cn);
        DataTable dt  =   new  DataTable();
        da.Fill(dt);
         return  dt;
    }

     ///   <summary>
     ///  为Tree添加新节点
     ///   </summary>
     ///   <param name="tblName"></param>
     ///   <param name="_TreeName"></param>
     ///   <param name="_TreeParentID"></param>
     ///   <param name="txtName"></param>
     ///   <param name="rootID"></param>
     public   static   void  InsertNode( string  tblName,  string  _TreeName,  string  _TreeParentID,  string  txtName, string  rootID)
    {
         using  (SqlConnection Conn  =  GetDB.GetConnect())
        {
            SqlCommand cmd  =   new  SqlCommand(String.Format( " insert into {0} ({1},{2}) values (@TreeName,@TreeParentID) " ,tblName,_TreeName,_TreeParentID), Conn);
            cmd.Parameters.Add( " @TreeName " , SqlDbType.NVarChar,  50 ).Value  =  txtName;
            cmd.Parameters.Add( " @TreeParentID " , SqlDbType.NVarChar,  50 ).Value  =  rootID;
            Conn.Open();
            cmd.ExecuteNonQuery();
            Conn.Close();
        }
    }
}

图：