Populate TreeView Menu with XML

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• Download source code - 22.3 KB

Introduction

Creating treeview menus on the fly from an XML file can be useful when the menu items are constantly being updated. For instance, when using an XML file as a database to store records in.

Here is a simple example of how to do this. The example is kept simple to avoid any confusion.

Background

A working knowledge of XML, the TreeView control, and the Visual Studio is helpful in understanding the steps.

Using the code

Note: The attached solution file (xml2treeviewmenuSolution) was created with VS2010.

Add an XML file to your project and name it "menu.xml". Edit the XML file with the menu items.

<?xml version="1.0" encoding="utf-8" ?>
<root>
<folder title='folder 1a' >
<record title='record 1a1' />
<record title='record 1a2' />
<folder title='folder 1b'>
<record title='record 1b1' />
</folder>
</folder>
<folder title='folder 2a' >
<record title='record 2a1' />
</folder>
<folder title='folder 3a' >
<record title='record 3a1' />
<record title='record 3a2' />
</folder>
</root>

Drag the TreeView control from the Visual Studio Toolbox onto your Windows form. In this example, I named the control "treeViewMenu".

Add references to the XML classes in your using statements.

using System.Xml;
using System.Xml.XPath;    

Create an XML document to hold the file.

public partial class Form1 : Form
{
    private XmlDocument docXML = new XmlDocument();

When the form is loaded, load the XML document with the XML file and begin populating the TreeView control.

private void Form1_Load(object sender, EventArgs e)
{
    docXML.Load("menu.xml"); // Load the xml file
    populateBaseNodes(); // Populate all of the base nodes
}

Population begins with the first level <folder> nodes. After each base node is added to the tree, the child nodes for the current base node are added.

private void populateBaseNodes()
{
    treeViewMenu.Nodes.Clear(); // Clear any existing items
    treeViewMenu.BeginUpdate(); // Begin updating the treeview
    TreeNode treenode;
    treenode = treeViewMenu.Nodes.Add("Folders");
    
    XmlNodeList baseNodeList = docXML.SelectNodes("root/folder");
    // Get all first level <folder> nodes

    foreach (XmlNode xmlnode in baseNodeList)
    // loop through all base <folder> nodes 
    {
        string title = xmlnode.Attributes["title"].Value;

        treenode = treeViewMenu.Nodes.Add(title); // add it to the tree

        populateChildNodes(xmlnode, treenode); // Get the children
    }

    treeViewMenu.EndUpdate(); // Stop updating the tree
    treeViewMenu.Refresh(); // refresh the treeview display
}

Each child node will be inspected for further children. The loop will called for each child node that was found.

private void populateChildNodes(XmlNode oldXmlnode, TreeNode oldTreenode)
{
    TreeNode treenode = null;
    XmlNodeList childNodeList = oldXmlnode.ChildNodes;
    // Get all children for the past node (parent)

    foreach (XmlNode xmlnode in childNodeList)
    // loop through all children
    {
        string title = xmlnode.Attributes["title"].Value;
        // add it to the parent node tree
        treenode = oldTreenode.Nodes.Add(title);
        populateChildNodes(xmlnode, treenode); 
    }
}

Points of interest

Fancy up your menu using an image list and add an icon attribute to your menu file.