Project needs, there is a tree menu requires dynamic generation, Lenovo TreeView control, decided to use TreeView to implement
First of all, I noticed that TreeView control has a property Treenodesrc
This property can specify an XML file in a fixed format.
XML Version = "1.0" encoding = "UTF-8"
?>
<
Treenodes
>
<
TREENODE
TEXT
= "aaaaaaaa"
Checkbox
= "True"
>
TREENODE
>
<
TREENODE
TEXT
= "bbbbbbbb"
Checkbox
= "True"
>
TREENODE
>
<
TREENODE
TEXT
= "cccccccccc"
Expanded
= "True"
Checkbox
= "True"
>
<
TREENODE
TEXT
= "DDDDDDDDD"
Checkbox
= "True"
>
TREENODE
>
<
TREENODE
TEXT
= "eeeeeeeee"
Checkbox
= "True"
>
TREENODE
>
TREENODE
>
<
TREENODE
TEXT
= "ffffffffffffffff"
Checkbox
= "True"
>
TREENODE
>
Treenodes
>
So I want to read the files in the database to write into an XML file, and then bind it.
Since it is an unlimited level menu, it must be recruited to achieve, so I wrote a recursive algorithm as follows.
Private
Void
Createxml (XmlDocument ObjroToToC, Xmlelement Objrootelem,
int
Belong)
{// get Dataset here's DataSet specific acquisition method I omitted DataSet DS = New Dataset (); Foreach (DataRow Dr in Ds.Tables [0] .ROWS) {// Create ChildNode Treenode Xmlelement ObjXMLEM = Objxmldoc.createElement ( "TREENODE"); objRootElem.AppendChild (objXmlElem); // Create Attributes text XmlAttribute objXmlAttText = objXMLDoc.CreateAttribute ( "text"); objXmlAttText.Value = dr [ "text"] ToString () Trim ();.. objXmlElem. setAttributeNode (objXmlAttText); // Create Attributes CheckBox XmlAttribute objXmlAttCB = objXMLDoc.CreateAttribute ( "CheckBox"); objXmlAttCB.Value = "True"; objXmlElem.SetAttributeNode (objXmlAttCB); int id = int.Parse (dr [ "id"] .Tostring (). Trim ()); CreateXML (Objxmldoc, ObjxmLem, ID);}} then use the following method to implement binding
Private
Void
Bindxmltree ()
{// Create Xml File XmlDocument objXmlDoc = new XmlDocument (); // Insert Xml Declaration XmlDeclaration objXmlDeclare = objXmlDoc.CreateXmlDeclaration ( "1.0", "UTF-8", "yes"); objXmlDoc.InsertBefore (objXmlDeclare, objXmlDoc.DocumentElement ); XmlElement objRootElem = objXmlDoc.CreateElement ( "TREENODES"); objXmlDoc.AppendChild (objRootElem); CreateXml (objXmlDoc, objRootElem, 0); objXmlDoc.Save ( "E: //TreeMenu.xml"); TreeView2.TreeNodeSrc = " TreeMenu.xml ";
I stopped until the last two lines, because the problem occurred that the generated objxmldoc file didn't know what to use to bind the Treenodesrc I tried to try the direct treeview2.treenodesrc = objxmldoc; but TreenodesRC is String data, no way there is no way Nothing method can bind directly to this objxmldoc file? So I changed a way to implement TreeView has a node control called Treenode, directly putting data on Treenode on Treenode.
Void
CreateTree
int
Belong, Microsoft.Web.ui.WebControls.treenode rootnode)
{DataSet DS = New Dataset (); Foreach (DATAROW DR IN DS.TABLES [0] .ROWS) {Microsoft.Web.ui.WebControls.treenode Treenode = New Microsoft.Web.ui.WebControls.treenode (); TREENODE. TEXT = DR ["text"]. TREENODE.CHECKBOX = true; rotnode.Nodes.add (Treenode); int ID = int.parse (DR ["ID" ] .ToString (). Trim ()); CreateTree (ID, TREENODE);}}
Use the same recursive ideas, and I found that this is more simple, many of the Treenode itself is very convenient to modify
If you have to use XML to add every property, trouble
Triggering this method in PageLoad
Private
Void
Page_load
Object
Sender, System.EventArgs E)
{Microsoft.Web.UI.WebControls.TreeNode rootnode = new Microsoft.Web.UI.WebControls.TreeNode (); rootnode.Expanded = true; TreeView2.Nodes.Add (rootnode); CreateTree (0, rootnode);}
Note that this is here to achieve recursion, you have to add an empty root node rootnode
This will make it roughly
In addition, the data format in the database is like this.
-----------------------------------------
ID text belong
1 aaaa 0
2 bbbb 0
3 CCCC 0
4 DDDD 1
5 Eeee 2
