获取所有检查节点及其子节点树状列表 [英] Get list of all checked nodes and its subnodes in treeview

问题描述

我有一个树状列表复选框，列表中包含的节点，子节点和子节点中的某些情况下，子节点。当用户检查一些项目，我想获得所选项目的列表

I have a treeview list check boxes and the list contains nodes, subnodes and in some cases subnode of subnode. When user check some items i want to get list of selected items.

在此，为什么我只得到selcted主节点的项目：

On this why I get only selcted items of main node:

 foreach (System.Windows.Forms.TreeNode aNode in tvSastavnica.Nodes)
        {
            if (aNode.Checked == true)
            {
                Console.WriteLine(aNode.Text);
            }
        }

如何通过整个树状特拉弗斯并得到检查的项目？子节点

How to travers through whole treeview and get checked items in subnodes?

推荐答案

如果您喜欢LINQ，你可以创建一个横贯整个树视图扩展方法：

If you like LINQ, you can create an extension method that traverses the whole treeview:

internal static IEnumerable<TreeNode> Descendants(this TreeNodeCollection c)
{
    foreach (var node in c.OfType<TreeNode>())
    {
        yield return node;

        foreach (var child in node.Nodes.Descendants())
        {
            yield return child;
        }
    }
}

然后就可以执行所有的操作您想使用LINQ。在你的情况，让选择的节点列表很简单：

Then you can perform every operations you want using LINQ. In your case, getting a list of selected nodes is easy:

var selectedNodes = myTreeView.Nodes.Descendants()
                    .Where(n => n.Checked)
                    .Select(n => n.Text)
                    .ToList();

这种方法的一个优点是它是通用的。

An advantage of this approach is it is generic.

不过，由于后代（）方法遍历整个树，它可能是一个有点比@mybirthname给出，因为它只关心那些与父母检查节点的答案效率较低。 。如果您的使用情况，包括这个约束我不知

However, because the Descendant() method traverses the whole tree, it might be a bit less efficient than the answer given by @mybirthname because it only cares about nodes that are checked with their parents. I dont known if your use case includes this constraint.

编辑：现在@mybirthname答案已被编辑，它这样做。现在你有循环和LINQ的解决方案，无论是递归的。

Now @mybirthname answer has been edited, it is doing the same. Now you have the loop and the LINQ solution, both are recursive.

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