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C# - Winforms - TreeView - Multiple Nodes

Apparently my question has been neglected so I am opening up a new question as I need a solution.

I have the Below code. It works fine for a TreeView with two nodes. I have three nodes that I am working on and need to expand it. So, it my data looks something like this.

- Level 1
- Sub Level 2
- Sub Sub Level 3

When I click on Sub Sub Level 3 I want all nodes above check if all nodes above "Sub Sub Level 3 are checked" and unchecked also (the reverse). Right now it will check "Sub Sub Level 3" and "Sub Level 2" but not "level 1". I also want all Nodes below Level 1 checked if Level 1 is checked.

        private void myTreeView_AfterCheck(object sender, TreeViewEventArgs e)
        {
            if (trvCheckLock)
            {
                return;
            }
            trvCheckLock = true;
            trvMessageType.BeginUpdate();
            try
            {
                TreeNode item = e.Node;
                //If the user checks/unchecks the node that has children,
                if (item.Nodes.Count &gt; 0)
                {
                    //All children are unchecked as well
                    foreach (TreeNode child in item.Nodes)
                    {
                        child.Checked = item.Checked;
                        UpdateObjectModel(item.Text, child.Text, child.Checked);
                    }
                }
                //Otherwise (if the item has a parent)
                if (item.Parent != null)
                {
                    //The parent node should be checked only when all its children 
                    //are checked too
                    if (!item.Checked)
                    {
                        item.Parent.Checked = false;
                    }
                    else
                    {
                        bool allChecked = true;
                        foreach (TreeNode sibling in item.Parent.Nodes)
                        {
                            if (!(allChecked = allChecked && sibling.Checked))
                            {
                                break;
                            }
                        }
                        item.Parent.Checked = allChecked;
                    }
                }
                //Update the list of the selected items to the right
                if (item.Parent != null)
                    UpdateSelected(item);
            }
            finally
            {
                trvMessageType.EndUpdate();
                trvCheckLock = false;
            }
        }

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Éric Moreau

Something like this:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        private Boolean trvCheckLock;

        public Form1()
        {
            InitializeComponent();

            trvMessageType.ExpandAll();
            trvMessageType.AfterCheck += myTreeView_AfterCheck;
        }

        private void myTreeView_AfterCheck(object sender, TreeViewEventArgs e)
        {
            if (trvCheckLock)
            {
                return;
            }
            trvCheckLock = true;
            trvMessageType.BeginUpdate();
            try
            {
                TreeNode item = e.Node;

                SetChildrenChecked(item, e.Node.Checked);
                SetParentChecked(item, e.Node.Checked);
            }
            finally
            {
                trvMessageType.EndUpdate();
                trvCheckLock = false;
            }
        }

        protected void SetChildrenChecked(TreeNode pNode, bool pChecked)
        {
            if (pNode.Nodes.Count > 0)
            {
                foreach (TreeNode node in pNode.Nodes)
                {
                    node.Checked = pChecked;
                    if (node.Nodes.Count>0)
                        SetChildrenChecked(node, pChecked);
                }
            }
        }

        protected void SetParentChecked(TreeNode pNode, bool pChecked)
        {
            if (pNode.Parent != null)
            {

                pNode.Parent.Checked = pChecked;
                SetParentChecked(pNode.Parent, pChecked);
            }
        }

    }
}

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CipherIS

ASKER

Overflow exception. Trying to figure it out.

ASKER CERTIFIED SOLUTION

it_saige

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Éric Moreau

have you tried just that code before trying to integrate your other call to UpdateObjectModel/...?