Question

I am using the following code to get the contents of a folder into a TreeView. But the current code always adds the contents to the root of the TreeView. It does not add them as child nodes of their parent folder’s node.

Can you help me?

void Recurse(string path)
{
    DirectoryInfo info = new DirectoryInfo(path);
    TreeNode root = new TreeNode(info.Name);
    string[] sub = Directory.GetDirectories(info.FullName);
    TreeNode node = new TreeNode();
    MailTree.Nodes.Add(root);
    if (sub.Length == 0) {

    }
    else
    {
        foreach(string i in sub)
        {       
            DirectoryInfo subinfo = new DirectoryInfo(i);                    
            root.Nodes.Add(subinfo.Name);                    
            Recurse(i);                  
        }
        //MailTree.Nodes.Add(root);
    }   
}

Answer 1

The recursive part of your function is always adding the child nodes to the root. You need to add in the “parent node” as a parameter of your recursive function. Something like this:

void Recurse(string path, TreeNode parentNode)
{
    DirectoryInfo info = new DirectoryInfo(path);
    TreeNode node = new TreeNode(info.Name);

    if (parentNode == null)
        MailTree.Nodes.Add(node);
    else
        parentNode.Nodes.Add(node);

    string[] sub = Directory.GetDirectories(path);
    if (sub.Length != 0)
    {
        foreach(string i in sub)
        {       
            Recurse(i, node);                  
        }
    }   
}