I just want to show checked node's values and I've got the following code regarding that

Default.aspx

 <asp:Literal ID="Message" runat="server"></asp:Literal>
    <asp:Button ID="Button1" runat="server" Text="Button" Width="56px" 
            OnClick="Select_Change" />
      <div>
     
          <asp:TreeView ID="TreeView1" runat="server" 
              ShowCheckBoxes="All"
              OnSelectedNodeChanged="Select_Change"
              >

          </asp:TreeView>
      </div>

Default.aspx.cs

protected void Page_Load(object sender, EventArgs e)
        { 
            //These variables and methods create a hierarchy of the folder structure.
            var latestDirectory = DirectoryList().First().FullName.ToString();
            
            this.directoryFiles = DirSearch(latestDirectory);
            this.directoryArray = dirArray;
            this.directoryString.Text = latestDirectory;

            ListDirectory(TreeView1, latestDirectory);
        }

protected void Select_Change(object sender, EventArgs e)
        {
            string message = "selected nodes \n";
            
            foreach(TreeNode item in TreeView1.CheckedNodes)
            {
                message  = item.Text;
            }
            Message.Text = message;
        }

When I click the button, it just shows the generic "selected nodes" with nothing after it, even after selected node(s). Any ideas as to what I'm missing here?

CodePudding user response：

The selected item, is just a item, you want the collection of checked values.

this:

    For Each tN As TreeNode In TreeView1.CheckedNodes
        Debug.Print("Sel node = " & tN.Value & "," & tN.Text)
    Next

or

    foreach (TreeNode tN in TreeView1.CheckedNodes) 
    {
        Debug.Print("Sel node = " & tN.Value & "," & tN.Text);
        message  = tN.Value.ToString()   "->"   tN.Text   "| "; 
    }

So, is your code beind setting both a value and text? Or perhaps you are just setting the .Value. It not clear how the TV is being loaded up?

EDIT ======================================================= Lets take an full example. We have this:

        <asp:TreeView ID="TreeView1" runat="server"
            ShowCheckBoxes="All">
        </asp:TreeView>

        <br />
        <asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" />
        <br />
        <asp:TextBox ID="TextBox1" runat="server" Width="347px"></asp:TextBox>

Code:

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
            LoadTree();
    }

    void LoadTree()
    {
        for (int i = 1; i <= 5; i  )
            TreeView1.Nodes.Add(new TreeNode("Tx "   i, "Vx"   i));
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        string sChoices = "";
        foreach (TreeNode tN in TreeView1.CheckedNodes)
            sChoices  = "("   tN.Value   ","   tN.Text   ") ";

        TextBox1.Text = sChoices;
    }

So, we run and check the first two, say like this: