asp.net c#Treeview 增加节点

asp教程.net c#treeview 增加节点
void  creat_node(string
name,microsoft.web.ui.webcontrols.treenode  t1,string  number)
        {
            //定义一个新的结点

            microsoft.web.ui.webcontrols.treenode  t2=new
microsoft.web.ui.webcontrols.treenode();
            t2.id=number;
            t2.text=name;
            //判断是否为根结点
            treeview1.expandedimageurl="images/depart03.bmp";
            if(t1.id.trim()=="###")
            {
                treeview1.nodes.add(t2);
                t2.imageurl="images/depart01.bmp";
            }
            else
            {
                t1.nodes.add(t2);
                   t2.imageurl="images/depart01.bmp";
                t1.imageurl="images/depart02.bmp";
            }

           //取得这个结点的所有子结点，利用递归自动生成
            string myselectquery = "select parentid, id,name from table1
where  parentid='" + number +"'";
            string myconnstring="provider=microsoft.jet.oledb.4.0;data
source="+server.mappath(".")+"/dt/mydata.mdb";
            oledbconnection myconnection = new
oledbconnection(myconnstring);
            oledbcommand mycommand = new
oledbcommand(myselectquery,myconnection);
            myconnection.open();
            oledbdatareader myreader;
            myreader = mycommand.executereader();
            while (myreader.read())
            {
                creat_node(myreader.getstring(2),t2,myreader.getstring(1));

            }
            myreader.close();
            myconnection.close();

        }

    private void createprovidertreebtn_click(object sender,
system.eventargs e)
        {
            microsoft.web.ui.webcontrols.treenode  t1=new
microsoft.web.ui.webcontrols.treenode();
            creat_node("",t1,"###");
   
2、增加根节点  
private   void menuitemaddroot_click(object   sender,   system.eventargs   e)  
{  
try  
{  
treenode   treenode=new   treenode("新节点");  
treenode.tag=maxrecordnumber(dataset.tables["tree"],"nodeid")+1;  
this.treeview.nodes.add(treenode);  
adddeletenode(treenode,rootnodetag,"add");  
treeview.selectednode   =   treenode   ;  
loadtreeview.loadtreenodeimage(treeview.selectednode,this.imagelist1,nodeimagemode);  
//执行指定节点的选定操作  
this.treeviewafterselect(treeview.selectednode   );  
menuitemrename_click(new   object(),new   system.eventargs());  
}  
catch(exception   te)  
{  
messagebox.show(this,te.message,"errorroot",messageboxbuttons.ok,messageboxicon.warning);  
}  
}

 
3、增加子节点  
private   void   menuitemaddchild_click(object   sender,   system.eventargs   e)  
{  
try  
{  
//1.当一个节点有对应链接资料时，不可以增加子节点  
//2.当一个节点有对应链接资料时，可以增加图片  
if   (this.ishavelinedata(dataset.tables["data"],this.richtextboxid))  
{  
messagebox.show(this,"要增加子节点，必须在这个节点没有可以链接的资料后才可以增加！","操作错误",messageboxbuttons.ok,messageboxicon.information   );  
return;  
}  
treenode   treenode=new   treenode("新节点");  
treenode.tag=maxrecordnumber(dataset.tables["tree"],"nodeid")+1;  
treeview.selectednode.nodes.add(treenode);  
adddeletenode(treenode,treeview.selectednode.tag.tostring(),"add");  
treeview.selectednode   =   treenode   ;  
loadtreeview.loadtreenodeimage(treeview.selectednode,this.imagelist1,nodeimagemode);  
//执行指定节点的选定操作  
this.treeviewafterselect(treeview.selectednode   );  
menuitemrename_click(new   object(),new   system.eventargs());  
}  
catch(exception   te)  
{  
messagebox.show(this,te.message,"errorchild",messageboxbuttons.ok,messageboxicon.warning);  
}  
}

 
4、增加兄弟节点  
private   void   menuitemaddborther_click(object   sender,   system.eventargs   e)  
{  
try  
{  
//判断是否选定组件中的根节点  
if   (treeview.selectednode.parent==null)  
{  
messagebox.show   ("节点<"+treeview.selectednode.text.trim()+   ">为根节点，要加入兄弟节点，请使用"加入根节点"选项！"   ,   "information"   ,   messageboxbuttons.ok   ,   messageboxicon.information   )   ;  
return;  
}  
treenode   treenode=new   treenode("新节点");  
treenode.tag=maxrecordnumber(dataset.tables["tree"],"nodeid")+1;  
treeview.selectednode.parent.nodes.add(treenode);  
adddeletenode(treenode,treeview.selectednode.parent.tag.tostring().trim(),"add");  
treeview.selectednode   =   treenode   ;  
loadtreeview.loadtreenodeimage(treeview.selectednode,this.imagelist1,nodeimagemode);  
//执行指定节点的选定操作  
this.treeviewafterselect(treeview.selectednode   );  
menuitemrename_click(new   object(),new   system.eventargs());  
}  
catch(exception   te)  
{  
messagebox.show(this,te.message,"errorparent",messageboxbuttons.ok,messageboxicon.warning);  
}  
} 

contextmenustrip1与treeview1关联，在节点上单击右键就给该节点添加子节点，在空白地方单击右键，就添加根节点
using system;
using system.collections.generic;
using system.componentmodel;
using system.data;
using system.drawing;
using system.text;
using system.windows.forms;

namespace windowsapplication8
{
    public partial class form1 : form
    {
        public form1()
        {
            initializecomponent();
            this.treeview1.labeledit = true;
        }

        private void treeview1_nodemouseclick(object sender, treenodemouseclickeventargs e)
        {
            if (e.button == mousebuttons.right)
            {
                this.treeview1.selectednode = e.node;
                flag = true;
                contextmenustrip1.show(mouseposition);
            }
        }
        bool flag = false;
        private void 添加节点toolstripmenuitem_click(object sender, eventargs e)
        {
            treenode tn = new treenode();
            if (flag)
            {
                this.treeview1.selectednode.nodes.add(tn);
                this.treeview1.selectednode = tn;
                tn.beginedit();
                flag = false;
            }
            else
            {
                this.treeview1.nodes.add(tn);
                this.treeview1.selectednode = tn;
                tn.beginedit();
                flag = false;
            }
        }

        private void treeview1_afterlabeledit(object sender, nodelabelediteventargs e)
        {
            e.node.text = e.label;
        }

        private void contextmenustrip1_opening(object sender, canceleventargs e)
        {
            if (!flag)
            {
                this.treeview1.selectednode = null;
            }
        }
        bool flag1 = false;
        private void contextmenustrip1_itemclicked(object sender, toolstripitemclickedeventargs e)
        {
            flag1 = true;
        }

        private void contextmenustrip1_closed(object sender, toolstripdropdownclosedeventargs e)
        {
            if (!flag1)
            {
                flag = false;
            }
            else
            {
                flag1 = false;
            }
        }

    }
}