CODEWITHSUNDEEP
c#.netwinformstreeview
Amit
Amit

Reputation: 22076

Why TreeView control creating blank node?

Frist see following code and images.

Code A

treeView1.Nodes.Add("Node A");
treeView1.Nodes.Add("Node B");

Output :
enter image description here


Code B

        TreeNode tn = new TreeNode();
        tn.Nodes.Add("Node A");
        tn.Nodes.Add("Node B");
        treeView1.Nodes.Add(tn);

enter image description here


Now my problem is that treeView1.Nodes.Add(tn); creating a blank node, but my requirement is like Code A's image type (without blank node). If you need any other information please let me know.
UPDATE
Actually Ithere is a function in my code which returns a TreeNode and I have to add this node to TreeView control without first blank level.

Upvotes: 2

Views: 1948

Answers (3)

John Fisher
John Fisher

Reputation: 22719

This code:

TreeNode tn = new TreeNode();

creates an actual item. You didn't give it any text, so it appears blank. Then next two lines are adding child nodes to the blank node.

If your goal is the code in "A", why are you writing "B"?

Edit: response to your updated question

You have a function returning a root blank tree node, which contains children you want. So, something like this is in order.

foreach (var node in returnedNode.Nodes)
{
    treeView1.Nodes.Add(node);
}

OR

treeView1.Nodes.AddRange(returnedNode.Nodes.Cast<TreeNode>().ToArray());

Upvotes: 5

sll
sll

Reputation: 62494

Name of the root node is empty because you've used default constructor of the TreeNode class.

Try out specifying name for the tn node using TreeNode(string text) constructor

    // specify name of the root node
    TreeNode tn = new TreeNode("Root Node Name");
    tn.Nodes.Add("Node A");
    tn.Nodes.Add("Node B");
    treeView1.Nodes.Add(tn);

UPDATE: Since question was updated

Just set Text property for node returned by a function:

TreeNode treeNode = YourMethodWhichCreatesTreeNode();
treeNode.Text = "Root Node Name";
treeView.Nodes.Add(treeNode);

Upvotes: 2

Wiktor Zychla
Wiktor Zychla

Reputation: 48230

TreeNode t1 = new TreeNode( "Node A" );         
treeView1.Nodes.Add( t1 );
TreeNode t2 = new TreeNode( "Node B" );         
treeView1.Nodes.Add( t2 );

You have to add nodes directly UNDER treeView1, not under it's child as in 2nd snippet.

Upvotes: 2

Related Questions