Asp.net 2.0 Treeview dynamic filling and unlimited level tree

Asp.net 2.0 Treeview is dynamically filled and an infinite level tree is implemented,
Keyword field of the database table:
Table: Table1

Type_id type_name per_type_id
0 Root directory- 1
1 Subdirectory 0
2 Subdirectory 2 0
3 Sub-Directories 2
.
9 Root directory 2- 1

C # Code 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 Tree: system. Web. UI. Page
{

Protected   Void Page_load ( Object Sender, eventargs E)
{

Treeview1.nodes. Clear ();

Datatable dt = Tree_table ();
Dataview dv =   New Dataview (DT );
DV. rowfilter =   " Type_id = 0 " ;

Foreach (Datarowview DRV In DV)
{
Treenode Node =   New Treenode ();
Node. Text = DRV [ " Type_name " ]. Tostring ();
Node. Value = DRV [ " Type_id " ]. Tostring ();
Node. navigateurl =   " ? S = "   + DRV [ " Type_id " ]. Tostring ();
Treeview1.nodes. Add (node );
Addchildnode (DT, node );
}


}

Private Datatable tree_table ()
{

// Hooyesdatalink is the data connection string key name in the configuration.
Sqlconnection con =   New Sqlconnection (configurationmanager. receivettings [ " Hooyesdatalink " ]);
Sqldataadapter SDA =   New Sqldataadapter ( " Select * From Table1 " , Con );
Datatable dt =   New Datatable ();
SDA. Fill (DT );
Return DT;
}

Recursion to implement an infinite level tree # Region Recursion to implement an infinite level tree
Private   Void Addchildnode (datatable DT, treenode node)
{
Dataview dv =   New Dataview (DT ); // Create a table view for dt
DV. rowfilter =   " Per_type_id =' "   + Node. Value +   " ' " ; // Filter
Foreach (Datarowview drv1 In DV)
{
Treenode childnode =   New Treenode ();
Childnode. Text = Drv1 [ " Type_name " ]. Tostring ();
Childnode. Value = Drv1 [ " Type_id " ]. Tostring ();
Childnode. navigateurl =   " ? S = "   + Drv1 [ " Type_id " ]. Tostring ();
Childnode. Expanded =   True ; // Show property is false

Node. childnodes. Add (childnode );


Addchildnode (DT, childnode );
}
}
# Endregion


}

Effect: