Question

我在VS 2012中使用.net c＃并尝试编写一个自动检查已检查父树视图节点的所有子节点的函数。我是c＃编程的新手，所以我发现了以下代码，但它有两个问题：

if（HasChildNodes（node））visual studio报告HasChildNodes的行未知。
我想从我单击检查的所选节点开始，我认为代码遍历整个树？

感谢您的帮助。

        treeView.BeginUpdate();
        //Loop through all the nodes of tree
        foreach (TreeNode node in treeView.Nodes)
        {
            //If node has child nodes
            if (HasChildNodes(node))
            {
                if (node.Checked == true)
                {
                    //Check all the child nodes.
                    foreach (TreeNode childNode in node.Nodes)
                    {
                        childNode.Checked = true;
                    }
                }
            }
        }
        treeView.EndUpdate();

Answer 1

以下是树视图示例的工作代码，包括检查和取消选中子节点和父节点（添加树视图并将名称指定为tvwDynamic）

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

命名空间Treeview { 公共部分类Form1：表格 { 公共Form1（） { 的InitializeComponent（）; }

    private void Form1_Load(object sender, EventArgs e)
    {
        TreeNode MainNode = new TreeNode("Java");
        tvwDynamic.Nodes.Add(MainNode);
        MainNode = new TreeNode("PHP");
        tvwDynamic.Nodes.Add(MainNode);           
        TreeNode node2 = new TreeNode("C#");
        TreeNode node3 = new TreeNode("VB.NET");
        TreeNode[] childNodes = new TreeNode[] {node2,node3};
        MainNode = new TreeNode("ASP.NET", childNodes);
        tvwDynamic.Nodes.Add(MainNode);
         TreeNode node4 = new TreeNode("Winforms");
        TreeNode node5 = new TreeNode("Webforms");
          TreeNode[] SubchildNodes = new TreeNode[] {node4,node5};
        MainNode =  new TreeNode("Test",SubchildNodes);
        tvwDynamic.Nodes[2].Nodes[1].Nodes.Add(MainNode);
        tvwDynamic.CheckBoxes = true;

    }

    private void tvwDynamic_AfterCheck(object sender, TreeViewEventArgs e)
    {
        if (e.Action != TreeViewAction.Unknown)
        {

            if (e.Node.Nodes.Count > 0)
            {

                /* Calls the CheckAllChildNodes method, passing in the current 

                Checked value of the TreeNode whose checked state changed. */

                this.CheckAllChildNodes(e.Node, e.Node.Checked);

            }

        }

        SelectParents(e.Node, e.Node.Checked);

    }
    private void CheckAllChildNodes(TreeNode treeNode, bool nodeChecked)
    {

        foreach (TreeNode node in treeNode.Nodes)
        {

            node.Checked = nodeChecked;

            if (node.Nodes.Count > 0)
            {

                // If the current node has child nodes, call the CheckAllChildsNodes method recursively.

                this.CheckAllChildNodes(node, nodeChecked);

            }

        }

    }


    private void SelectParents(TreeNode node, Boolean isChecked)
    {
        var parent = node.Parent;

        if (parent == null)
            return;

        if (!isChecked && HasCheckedNode(parent))
            return;

        parent.Checked = isChecked;
        SelectParents(parent, isChecked);
    }

    private bool HasCheckedNode(TreeNode node)
    {
        return node.Nodes.Cast<TreeNode>().Any(n => n.Checked);
    }
} }

Answer 2

这是一个可以在Visual Studio的Designer中使用的简单控件：

public class BetterTreeView : TreeView
{
    /// <summary>
    /// Whether to apply Checked property changes to child nodes.
    /// </summary
    public bool TickChildNodes { get; set; }

    protected override void OnAfterCheck(TreeViewEventArgs e)
    {
        base.OnAfterCheck(e);

        if (TickChildNodes)
        {
            foreach (TreeNode node in e.Node.Nodes)
            {
                node.Checked = e.Node.Checked; // Triggers OnAfterCheck (recursive)
            }
        }
    }
}

Answer 3

 treeview1.BeginUpdate();
 foreach (TreeNode tn in e.Node.Nodes)
     tn.Checked = e.Node.Checked;
 treeview1.EndUpdate();

这对我有用。你必须在AfterCheck EventHandler中添加这段代码。

Answer 4

没有与HasChildNodes相关的任何TreeView方法，您在这里与XML内容混淆。

public void CheckNodes(TreeNode startNode){
   startNode.Checked = true;
   foreach(TreeNode node in startNode.Nodes)
      CheckNodes(node);       
}        
//then you can call the method above with the TreeNode you check
CheckNodes(yourNode);

Answer 5

检查是否有子节点就足以检查

node.FirstNode != null

至于你的第二个问题，看起来你的代码检查了洞树，而不仅仅是从给定的节点，然后我再次需要查看整个方法签名以及在哪里保留按下的节点。如果您在myMember之类的会员中拥有该广告，请使用treeView更改该方法中的myMember：

    treeView.BeginUpdate();
    //Loop through all the nodes of tree
    foreach (TreeNode node in myMember.Nodes)
    {
        //If node has child nodes
        if (node.FirstNode != null)
        {
            if (node.Checked == true)
            {
                //Check all the child nodes.
                foreach (TreeNode childNode in node.Nodes)
                {
                    childNode.Checked = true;
                }
            }
        }
    }
    treeView.EndUpdate();

Answer 6

更正了foreach循环：

foreach (TreeNode node in treeView1.Nodes)
        {
            //If node has child nodes
            if (node.Checked == true)   //it is better to first check if it is "checked" then proceed to count child nodes
            {
                if (node.GetNodeCount(false) > 0)   //check if node has any child nodes
                {
                    //Check all the child nodes.
                    foreach (TreeNode childNode in node.Nodes)
                    {
                        childNode.Checked = true;
                    }
                }
            }
        }

Answer 7

检查父节点是否被检查。

然后遍历所有子节点。

if(e.Node.Checked==true)
            {
                foreach (TreeNode tn in e.Node.ChildNodes)
                {
                    tn.Checked = true;
                }
            }

选中父节点时自动检查子节点

7 个答案: