C＃treeView，当用户单击子节点时如何获取父节点

Question

I have a treeview which is generated programatically when documents are loaded into my programme.

My treeview looks something like this:

+ System - 65
        + Subsystem - 32
          Subsystem - 68
                       + Subsubsystem - 01
                         Subsubsystem - 02

+ System - 70
        + Subsystem - 22
          Subsystem - 30
                       + Subsubsystem - 10

I need to be able to click on a 'Subsubsystem' child node and have it poplulate my listView with all documents that belong to the respective System and subsystem. So for example, if i were to click on the Subsubsystem 10 of the treeview above, i need it to return all documents which are part of System 70, Subsystem 30 and Subsubsystem 10.

The bit i'm struggling with is knowing how to get the parent nodes of the Subsubsystem 10 when i click on it.

Obviously when i click on the Subsubsystem 10 my programme needs to get the parent nodes in order to return the documents belonging to the respective system and subsystem.

Any ideas?

Answer 1

Use the afterselect event of your treeview. In the TreeViewEventArgs, there is your current node. That node has a property parent.

private void treeView_AfterSelect(object sender, TreeViewEventArgs e)
{
    e.Node.Parent
}

Answer 2

you can use TreeNode.Parent Property on AfterSelect event

private void treeView1_AfterSelect(object sender, TreeViewEventArgs e)
{  

   if(e.Node.Parent!= null && 
     e.Node.Parent.GetType() == typeof(TreeNode) )
   {
      // do something with e.Node.Parent
   }
   else
   {
     //"No parent node.";
   }
}

Or you can get the parent from treeView1.SelectedNode.Parent

Answer 3

I use a simple loop to do this

    private TreeNode[] GetParentNodes(TreeNode node_)
    {
        TreeNode[] nodes_ = new TreeNode[node_.Level +1];
        nodes_[0] = node_;
        for (int i = 1; i < nodes_.Length; i++)
        {
            nodes_[i] = nodes_[i -1].Parent;
        }
        return nodes_;
    }

and call it from the click event (right click in my case) of the tree

private void treeView1_MouseDown(object sender, MouseEventArgs e)
    {
        if (e.Button == System.Windows.Forms.MouseButtons.Right)
        {
            processClick(e);
        }
    }

    private void processClick(System.Windows.Forms.MouseEventArgs e)
    {

        System.Drawing.Point p = new System.Drawing.Point(e.X, e.Y);

        TreeNode node = treeView1.GetNodeAt(p);
        treeView1.SelectedNode = node;

    }

It can be cleaned up significantly, but the general idea works.