I want to show all children of the first level on the treeview by default.
And then expand all children of those on click.
Try:
foreach (TreeNode tn in treeView1.Nodes) {
tn.Expand();
}
When adding nodes during runtime, you can just check the level and expand, if needed:
private void ShouldAutoExpand(TreeNode tn) {
if (tn.Level == 0)
tn.Expand();
}
There is no NodeAdded event you can hook into to check that automatically. You would have to determine yourself whether or not a node should be expanded "by default".
Update:
From your comment, it seems like you want to have all level 0 nodes expanded, but then expand all child nodes of level 1 when you expand them.
Try subscribing to the BeforeExpand event with this code:
private void treeView1_BeforeExpand(object sender, TreeViewCancelEventArgs e) {
treeView1.BeforeExpand -= treeView1_BeforeExpand;
if (e.Node.Level == 1) {
e.Node.ExpandAll();
}
treeView1.BeforeExpand += treeView1_BeforeExpand;
}
you can try something like this.. you will have to change the example to fit your own code since you neglected to paste any code that you have or attempted
private void addChildNode_Click(object sender, EventArgs e)
{
var childNode = textBox1.Text.Trim();
if (!string.IsNullOrEmpty(childNode)) {
TreeNode parentNode = treeView2.SelectedNode ?? treeView2.Nodes[0];
if (parentNode != null) {
parentNode.Nodes.Add(childNode);
treeView2.ExpandAll();
}
}
}
if you want a recursive, try this:
void expAll(TreeNode node)
{
node.Expand();
foreach(TreeNode i in node.Nodes)
{
expAll(i);
}
}
private TreeNode ExpandUptoLevel(TreeNode tn,int level)
{
if (level != 0)
{
level --;
tn.Nodes[0].Expand();
return ExpandUptoLevel(tn.FirstNode, level);
}
return tn;
}
To expand all nodes in a tree to a level the above code does not work. Just add a check to read and compare the actual node level to the level that you wish to expand to. Here's a code snippet.
private void ExpandUptoLevel(TreeNode tn, int level)
{
if (level >= tn.Level)
{
tn.Expand();
foreach (TreeNode i in tn.Nodes)
{
ExpandUptoLevel(i,level);
}
}
}
Only to open the first nodes:
for (int i = 0; i< treeView1.Nodes.Count; i++)
{
treeView1.Nodes[i].Expand();
}
Related
How to get certain rows from TreeView with all sub rows and fill them into another treeView in c# syncfusion?
Thank you
If I've got your point and assuming that you are copying nodes from WindowsForms TreeViews the following code may helps :
private void Form1_Load(object sender, EventArgs e)
{
MoveNodes(treeView1,treeView2,1, 2);
}
void AddRootNode(TreeView tree, TreeNode node)
{
var newNode = new TreeNode(node.Text);
tree.Nodes.Add(newNode);
foreach (TreeNode child in node.Nodes)
AddChildNode(newNode, child);
}
void AddChildNode(TreeNode parent, TreeNode node)
{
var newNode = new TreeNode(node.Text);
parent.Nodes.Add(newNode);
foreach (TreeNode child in node.Nodes)
AddChildNode(newNode, child);
}
private void MoveNodes(TreeView source,TreeView destination, params int[] indexes)
{
foreach (var index in indexes)
{
if (index < 0 || index >= source.Nodes.Count)
continue;
AddRootNode(destination, source.Nodes[index]);
}
}
I want to traverse through a treeview & set the value property to be its position in the tree as shown below
A[val:1]->A1[val:11]
l l--->A2[val:12]
l----->A3[val:13]
B[val:2]->B1[val:21]
l l--->B2[val:22]
C[val:3]->C1[val:31]
l l--->C2[val:32]
I have written a recursive which returns me all the nodes but i am unable to assign the desired position to its nodes.
private void TraverseTreeNode(TreeNodeCollection nodes)
{
foreach (TreeNode node in nodes)
{
TraverseTreeNode(node.ChildNodes);
}
}
Considering that TreeNode.Value is of type string, this will, starting at level = 1:
private static void TraverseTreeNode(TreeNodeCollection nodes, int parentNumber)
{
var childNumber = 1;
foreach (TreeNode node in nodes)
{
node.Value = string.Format("{0}{1}", parentNumber, childNumber ).Substring(0,node.Depth+1);
TraverseTreeNode(node.ChildNodes, parentNumber);
childNumber++;
if (node.Depth == 0) { parentNumber++; }
}
}
Only works for two levels but is easily extendable by adding additional parameters to TraverseTreeNode.
UPDATE
The following will work for any depth in hierarchy:
private static void TraverseTreeNode(TreeNodeCollection nodes, int parentNumber)
{
var childNumber = 1;
foreach (TreeNode node in nodes)
{
node.Value = node.Parent != null && node.Parent.Value != null
? string.Format("{0}{1}", node.Parent.Value, childNumber)
: string.Format("{0}{1}", parentNumber, childNumber).Substring(0, node.Depth + 1);
TraverseTreeNode(node.ChildNodes, parentNumber);
childNumber++;
if (node.Depth == 0) { parentNumber++; }
}
}
As you need recursive method, try this
private void Caller()
{
TraverseTreeNode(treeView1.Nodes);
}
private void TraverseTreeNode(TreeNodeCollection nodes)
{
int index = 1;
foreach (TreeNode node in nodes)
{
node.Text = (node.Parent != null ? node.Parent.Text : string.Empty) + index++;
TraverseTreeNode(node.Nodes);
}
}
i got this tree view and i made it to select all children if parent is checked, the way back as well. There's another rule to check some dependent child too. The problem is: I want to check the parent if any child is checked, but because those other rules i can't find a way to do that without the rules get conflict. So here's is the code i've made until now:
private void tvMorgan_AfterCheck(object sender, TreeViewEventArgs e)
{
//Check Children if parent checked
if (e.Node.Nodes.Count > 0)
{
TreeNode tnParent = e.Node;
if (tnParent.Checked)
{
foreach (TreeNode tnChild in tnParent.Nodes)
{
tnChild.Checked = true;
}
}
//Unchecked children if parent unchecked
else
{
foreach (TreeNode tnChild in tnParent.Nodes)
{
tnChild.Checked = false;
}
}
}
//If dependent node is selected, check the other two
else if (((e.Node.Text.Contains("BRL/EUR")) && (e.Node.Checked)) && (e.Node.Parent.Text.Contains("FWD")))
{
TreeNode tnParent = e.Node.Parent;
foreach (TreeNode tn in tnParent.Nodes)
{
if (tn.Text.Contains("BRL/USD") || tn.Text.Contains("EUR/USD"))
tn.Checked = true;
}
}
//If one of the two necessary nodes are uncheked, then uncheck the dependent one
else if ((((e.Node.Text.Contains("BRL/USD")) || (e.Node.Text.Contains("EUR/USD"))) && (!e.Node.Checked)) && (e.Node.Parent.Text.Contains("FWD")))
{
TreeNode tnParent = e.Node.Parent;
foreach (TreeNode tn in tnParent.Nodes)
{
if (tn.Text.Contains("BRL/EUR"))
tn.Checked = false;
}
}
}
Thanks in advance
The documentation of the TreeView.AfterCheck Event shows exactly how to do what you are looking for
I have treenode & i would like to find the deepest child in the treenode.
if there are 2 child nodes with level 11 & level 13 respectively then i need unction to return me the value 13.
How can i do that ?
public int FindLevel(TreeNode oParentNode)
{
counter++;
forech(TreeNode oSubNode in oParentNode.Nodes)
{
FindLevel(oParentNode);
}
return Counter;
}
Here is my suggestion for you:
private int GetDeepestChildNodeLevel(TreeNode node)
{
var subLevel = node.Nodes.Cast<TreeNode>().Select(GetDeepestChildNodeLevel);
return subLevel.Count() == 0 ? 1 : subLevel.Max() + 1;
}
here with explicit types:
private int GetDeepestChildNodeLevel(TreeNode node)
{
var subLevel = node.Nodes.Cast<TreeNode>().Select<TreeNode, int>(subNode => GetDeepestChildNodeLevel(subNode));
return subLevel.Count<int>() == 0 ? 1 : subLevel.Max() + 1;
}
Here's the extension method for TreeView that returns Level of the deepest node in that TreeView.
public int GetDeepestNodeLevel(this System.Windows.Forms.TreeView treeView)
{
int level = -1;
foreach (System.Windows.Forms.TreeNode node in treeView.Nodes) {
int deep = DigInNodes(node);
if (deep > level)
level = deep;
}
return level;
}
private int DigInNodes(System.Windows.Forms.TreeNode node)
{
int level = node.Level;
foreach (System.Windows.Forms.TreeNode subnode in node.Nodes) {
int deep = DigInNodes(subnode);
if (deep > level)
level = deep;
}
return level;
}
Code is tested and works for me.
This is the fast way to get level´s deep of selected node.
private void treeView1_AfterSelect(object sender, TreeViewEventArgs e)
{
TreeNode node = treeView1.SelectedNode;
MessageBox.Show(string.Format("You selected: {0}{1}", node.Text,e.Node.Level));
}
I would like to change the order of System.Windows.Forms.TreeNodes on the same level.
any suggestions on how this might be done in .net-2.0.
You need to manipulate the TreeView's Nodes collection. See TreeNodeCollection.
If you have three tree nodes and you want to move the last one to the front, for example: (Note: not tested code, but shows the idea)
var lastNode = MyTreeView.Nodes[2];
MyTreeView.Nodes.Remove(lastNode);
MyTreeView.Nodes.Insert(0, lastNode);
void MoveNodeUp(TreeNode node)
{
TreeNode parentNode = node.Parent;
int originalIndex = node.Index;
if (node.Index == 0) return;
TreeNode ClonedNode = (TreeNode)node.Clone();
node.Remove();
parentNode.Nodes.Insert(originalIndex - 1, ClonedNode);
parentNode.TreeView.SelectedNode = ClonedNode;
}
That's what I've written:
public void MoveNode(TreeView tv, TreeNode node, bool up)
{
if ((node.PrevNode == null) && up) {
return;
}
if ((node.NextNode == null) && !up) {
return;
}
int newIndex = up ? node.Index - 1 : node.Index + 1;
var nodes = tv.Nodes;
if (node.Parent != null) {
nodes = node.Parent.Nodes;
}
nodes.Remove(node);
nodes.Insert(newIndex, node);
}
I wrote this code which does not require any cloning.
For my case it moves up one position in the sibling nodes but can be adapted
TreeNode selectedNode = treeViewChain.SelectedNode;
if (selectedNode != null && selectedNode.Index > 0)
{
TreeNode parent = selectedNode.Parent;
int selectedIndex = selectedNode.Index;
selectedNode.Remove();
parent.Nodes.Insert(selectedIndex - 1, selectedNode);
treeViewChain.SelectedNode = selectedNode;
}