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Xml TreeView

23. Mar, 2007 by admin 0 Comments

The application shown here was my firstadventure into Xml in the .Net platform. My goal was to be able toreflect any Xml file into the Windows Forms TreeView control. I foundvarious examples online, but none I found were suited for opening allXml files, rather they were suited to one schema or another.

The problem I ran into while writing this was more of a programmingtheory issue than a coding issue. This example deals with two instancesof recursion, one for reading the Xml file in and one for adding thedata correctly to the TreeView control. I am aware that thisapplication reinvents the wheel, since Internet Explorer gives theexact same functionality, but I was more interested in learning how towork with Xml files within the .Net Platform, especially using theXmlDocument class and this seemed like a good start.

The following code snippet shows the method I used to accomplish my goal.

private void FillTree(XmlNode node, TreeNodeCollection parentnode)
{
// End recursion if the node is a text type
if(node == null || node.NodeType == XmlNodeType.Text || node.NodeType == XmlNodeType.CDATA)
return;

TreeNodeCollection tmptreenodecollection = AddNodeToTree(node, parentnode);

// Add all the children of the current node to the treeview
foreach(XmlNode tmpchildnode in node.ChildNodes)
{
FillTree(tmpchildnode, tmptreenodecollection);
}
}

private TreeNodeCollection AddNodeToTree(XmlNode node, TreeNodeCollection parentnode)
{
TreeNode newchildnode = CreateTreeNodeFromXmlNode(node);

// if nothing to add, return the parent item
if(newchildnode == null) return parentnode;

// add the newly created tree node to its parent
if(parentnode != null) parentnode.Add(newchildnode);

return newchildnode.Nodes;
}

private TreeNode CreateTreeNodeFromXmlNode(XmlNode node)
{
TreeNode tmptreenode = new TreeNode();

if((node.HasChildNodes) && (node.FirstChild.Value != null))
{
tmptreenode = new TreeNode(node.Name);
TreeNode tmptreenode2 = new TreeNode(node.FirstChild.Value);
tmptreenode.Nodes.Add(tmptreenode2);
}
else if(node.NodeType != XmlNodeType.CDATA)
{
tmptreenode = new TreeNode(node.Name);
}

return tmptreenode;
}

image1 Xml TreeView

About the Author: James Divine(james@4divine.com) is a Senior Software Developer with over 12 yearsexperience working with web programming, desktop applicationprogramming, server application programming and handheld deviceprogramming. He has been working in .Net and C# for more than twoyears. James currently holds a Microsoft Certified Professionalcertification and is working towards the MCSD.