ASP. NET Treeview operation instance (Code debugging passed)

This instance completes the Treeview addition and modification function, and deletes the bound dropdownlist mobile function.

. Aspx code

<Form ID = "form1" method = "Post" runat = "server">
<Font face = "">
<Table id = "Table1" cellspacing = "1" cellpadding = "1"

Width = "700" border = "1">
<Tr>
<TD style = "width: 168px"> </TD>
<TD> Treeview operation instance </TD>
</Tr>
<Tr>
<TD style = "width: 168px" valign = "TOP">
<Iewc: Treeview id = "treeview1"

Runat = "server"> </iewc: Treeview> </TD>
<TD valign = "TOP">
<Table id = "Table2" cellspacing = "1"

Cellpadding = "1" width = "100%" border = "0">
<Tr>
<TD> node name
<Asp: textbox

Id = "textbox1" runat = "server"> </ASP: textbox> </TD>
</Tr>
<Tr>
<TD>
<Asp: button

Id = "addbutton" runat = "server" text = ""> </ASP: button>
<Asp: button

Id = "editbutton" runat = "server" text = "modify"> </ASP: button>
<Asp: button

Id = "delbutton" runat = "server" text = "delete"> </ASP: button> </TD>
</Tr>
<Tr>
<TD> mobile nodes </TD>
</Tr>
<Tr>
<TD> the node to be moved

<Asp: dropdownlist id = "dropdownlist1" runat = "server"> </ASP: dropdownlist> </TD>
</Tr>
<Tr>
<TD>
<Asp: button

Id = "movebutton" runat = "server" text = "mobile"> </ASP: button> </TD>
</Tr>
</Table>
</TD>
</Tr>
<Tr>
<TD style = "width: 168px"> </TD>
<TD> </TD>
</Tr>
</Table>
</Font>
</Form>

. Aspx. CS code

Using Microsoft. Web. UI. webcontrols;
Private void page_load (Object sender, system. eventargs E)
{
// Place user code here to initialize the page
If (! Page. ispostback ){
Button del = new button ();
Del = (button) page. findcontrol ("delbutton ");
Del. Attributes. Add ("onclick", "Return confirm ('Confirm delete ');");
Showlist ();
}
}
Private void showlist (){
// Bind the Treeview
// Infobase IO = new Infobase ();
Dropdownlist1.items. Clear ();
Listitem list = new listitem ();
List. value = "0 ";
List. Text = "all categories ";
Dropdownlist1.items. Add (list );

// Add the root node
Treeview1.nodes. Clear ();
Treenode node = new treenode ();
Node. Text = "category list ";
Node. Target = "0 ";
Node. Expanded = true;
Treeview1.nodes. Add (node );
Treeshow (0, node );
Treeview1.databind ();
}

Private void treeshow (INT parterid, treenode) {// recursive category
//
Dataset DS = returndataset (parterid );
If (Ds! = NULL)
{
For (INT I = 0; I <Ds. Tables [0]. Rows. Count; I ++)
{
Treenode node = new treenode ();
Node. Target = Ds. Tables [0]. Rows [I] ["ID"]. tostring ();
Node. Text = Ds. Tables [0]. Rows [I] ["name"]. tostring ();
Treenode. nodes. Add (node );
Node. Expanded = true;
Dataset ds2 = returndataset (int32.parse (Ds. Tables

[0]. Rows [I] ["ID"]. tostring ()));
If (ds2.tables [0]. Rows. Count> 0)
{
Treeshow (int32.parse (Ds. Tables [0]. Rows [I]

["ID"]. tostring (), node );
}
}
}
}

Private dataset returndataset (INT parterid ){
Oledbconnection conn = new oledbconnection ();
Conn. connectionstring = "provider = Microsoft. Jet. oledb.4.0; Data

Source = "+ server. mappath (" data. mdb ");
Oledbdataadapter cmd;
Dataset DS = new dataset ();
Try
{
Conn. open ();
Cmd = new oledbdataadapter ("select * From Treeview where

Parterid = "+ parterid +" order by createtime ASC ", Conn );
Cmd. Fill (DS );
}
Catch (exception ex)
{
Response. Write (ex. tostring ());
Response. End ();
}
Finally {
Conn. Dispose ();
}
Return Ds;
}

Private void addbutton_click (Object sender, system. eventargs E)
{// Add a node
If (textbox1.text! = "")
{
Treenode = treeview1.getnodefromindex

(Treeview1.selectednodeindex );
String [] treedepth = treenode. getnodeindex (). Split ('.');
If (treenode. Target! = NULL)
{
Int depth = treedepth. Length-1; // obtain the depth
Int parterid = int32.parse (treenode. Target); // obtain the parent class

ID
String classname = textbox1.text; // obtain the class name
Oledbconnection conn = new oledbconnection ();

Conn. connectionstring = "provider = Microsoft. Jet. oledb.4.0; Data Source =" + server. mappath

("Data. mdb ");
Conn. open ();
Oledbcommand cmd = new oledbcommand ();
Cmd. commandtype = commandtype. text;
Cmd. Connection = conn;
Cmd. commandtext = "insert into Treeview

(Name, parterid, depth) values ('"+ classname +"', "+ parterid +", "+ depth + ")";
Try
{
Cmd. executenonquery ();
Response. Write ("<SCRIPT> alert ('add

'); Location. href = 'treeviewstudy. aspx'; </SCRIPT> ");
Response. End ();
}
Catch (exception ex)
{
Response. Write (ex. tostring ());
Response. End ();
}
Finally
{
Cmd. Dispose ();
Conn. Dispose ();
}
}
Else {
// Response. Write (treenode. Target + "123 <br> ");
}
}
Else {
Response. Write ("enter a category and select a node ");
}
}

Private void editbutton_click (Object sender, system. eventargs E)
{// Modify a node
If (textbox1.text! = "")
{
Treenode = treeview1.getnodefromindex

(Treeview1.selectednodeindex );
Int id = int32.parse (treenode. Target );
String classname = textbox1.text;
If (treenode. Target! = NULL)
{
Oledbconnection conn = new oledbconnection ();

Conn. connectionstring = "provider = Microsoft. Jet. oledb.4.0; Data Source =" + server. mappath

("Data. mdb ");
Conn. open ();
Oledbcommand cmd = new oledbcommand ();
Cmd. commandtype = commandtype. text;
Cmd. Connection = conn;
Cmd. commandtext = "Update Treeview set

Name = '"+ classname +" 'where id = "+ ID;
Try
{
Cmd. executenonquery ();
Response. Write ("<SCRIPT> alert ('modified

'); Location. href = 'treeviewstudy. aspx'; </SCRIPT> ");
Response. End ();
}
Catch (exception ex)
{
Response. Write (ex. tostring ());
Response. End ();
}
Finally
{
Cmd. Dispose ();
Conn. Dispose ();
}
}
Else {}
}
Else
{
Response. Write ("enter a category and select a node ");
}
}

Private void delbutton_click (Object sender, system. eventargs E)
{// Delete
Treenode = treeview1.getnodefromindex

(Treeview1.selectednodeindex );
Int id = int32.parse (treenode. Target );
If (treenode. Target! = "0 ")
{
}
Else {
Response. Write ("root node cannot be deleted ");
}
}