.net, Development

Selectively removing checkboxes in a .NET 1.1 / 2.0 TreeView

25 Comments

Earlier this month, I had the need to customise a TreeView control such that it had checkboxes against some, not all, of the nodes.

Here’s a screenshot of what I wanted:

Treeview

It requires a little bit of code to achieve this effect, but is was worth the effort. Here’s the code that performs the magic:

[code lang=”C#”]
using System.Runtime.InteropServices;

namespace Treeview___CheckBoxes
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e)
{
// Iterate over the root nodes, removing their checkboxes
for (int n = 0; nTechnorati Tags: , , ,

25 thoughts on “Selectively removing checkboxes in a .NET 1.1 / 2.0 TreeView”

  1. Hi ,
    I need to implement similar kind of functinality for my treeview control.
    Could you please explain me in little more detail Form_Load function and TVITEM struct.

    Thanks in advance

  3. Hi, Craig.
    Thank you for this article. I’ve been searching for a solution of specified problem. I’ve tested your code example, it works.
    But there is 1 remark: when I select node without checkbox and press bar, checkbox appears again. Should I repeat this procedure on KeyPress event handler, or there is another way?

    Thank you in advance

  4. P.S. More precisely, when I select tree node without checkbox and press SPACE bar, checkbox appears again.

    Thank you

  5. I suppress the spacebar keydown event to avoid that behaviour, tell me if you find a better solution.

    void treeview_KeyDown(object sender, KeyEventArgs e)
    {
    if (e.KeyCode == Keys.Space)
    {
    e.SuppressKeyPress = true;
    }
    }

  6. I really thank you.
    I’ve solved the same problem with your code.

  7. Thank you for your help!
    I’ve solved the same problem with your code.

  10. Excellent work. I’ve modified it slightly for my own purposes and it works very well. Thanks for you post and effort.

    -Jamie Adams GIS Programmer/Analyst

  11. Awesome.. code works pretty sleek.. i have researching on this issue from quite a while.. thanks a lot..

  12. Can someone please convert this code to VB.NET? I have tried a code converter and it failed.

    Thanks
    -Matt

  19. Pingback: How to remove parent node checkbox of the Treeview « Powertips

  23. Thanks, works well with me.

    I made a recursive function out of it. I can hide one or more spécific levels.

  24. VB.net:

    Public Declare Function SendMessage Lib “user32” Alias “SendMessageA” (ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr

    Public Const TVIF_STATE As Integer = &H8
    Public Const TVIS_STATEIMAGEMASK As Integer = &HF000
    Public Const TV_FIRST As Integer = &H1100
    Public Const TVM_SETITEM As Integer = TV_FIRST + 63

    Public Structure TVITEM
    Public mask As Integer
    Public hItem As IntPtr
    Public state As Integer
    Public stateMask As Integer
    Public lpszText As String
    Public cchTextMax As Integer
    Public iImage As Integer
    Public iSelectedImage As Integer
    Public cChildren As Integer
    Public lParam As IntPtr
    End Structure

    Function RemoveCheckboxesOnRootNodes() As Boolean
    For n = 0 To TV1.Nodes.Count – 1
    Dim node As TreeNode = TV1.Nodes(n)
    Dim tvItem As New TVITEM
    tvItem.hItem = node.Handle
    tvItem.mask = TVIF_STATE
    tvItem.stateMask = TVIS_STATEIMAGEMASK
    tvItem.state = 0
    Dim lparam As IntPtr
    lparam = Marshal.AllocHGlobal(Marshal.SizeOf(tvItem))
    Marshal.StructureToPtr(tvItem, lparam, False)
    SendMessage(TV1.Handle, TVM_SETITEM, IntPtr.Zero, lparam)
    Next
    End Function

  25. It works also under .Net 4.0
    Thank you very much!

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