循环遍历所有树视图项 [英] Loop through all treeview items recursive

问题描述

我需要一个循环遍历所有TreeViewItems的函数，并为Beak提供具有特定标题的TreeViewItem ...



例如：

$ / $

I need a function which loops through all TreeViewItems and give beak the TreeViewItem which got a specific Header...

For example:

GetSearchedTreeViewItemByHeader(string _header)
{
  var searchedNode = new TreeViewItem();
  foreach(var node in treeView.Items)
  {
   if(node.Header == _header)
   {
    searchedNode = node
   }
  }

  return searchedNode
}

这仅适用于第一项treeView，有谁知道我如何遍历所有项目（也是所有的子项目......）？我不知道我只是从递归解决方案中听到但我不知道怎么做...



提前感谢！





编辑：

我使用WPF



我尝试过：



TreeViewItems.Items检查，for循环，while循环

this only works for the first Item in the treeView, does anybody know how i loop through all items(also all childitems...)? i got no idea i only heard from a recursive solution but i dont know how to do it...

thanks in advance!



I use WPF

What I have tried:

TreeViewItems.Items check, for loop, while loop

推荐答案

该任务的递归如此常见甚至微软已发布一个recursice代码片段。



提示：如果搜索特定项目，则将其用作附加输入参数。

The recursion on that task is so common that even Microsoft has published a recursice code snippet.

tip: if you search a specific item, you use it as additional input parameter.

这是迭代任何层次结构中所有节点的通用扩展方法：

Here's a generic extension method to iterate all nodes in any hierarchy:

private static IEnumerable<T> SelectRecursiveIterator<T>(IEnumerable<T> source, Func<T, IEnumerable<T>> getChildren)
{
    var stack = new Stack<IEnumerator<T>>();

    try
    {
        stack.Push(source.GetEnumerator());
        while (stack.Count != 0)
        {
            IEnumerator<T> iter = stack.Peek();
            if (iter.MoveNext())
            {
                T current = iter.Current;
                yield return current;

                IEnumerable<T> children = getChildren(current);
                if (children != null) stack.Push(children.GetEnumerator());
            }
            else
            {
                iter.Dispose();
                stack.Pop();
            }
        }
    }
    finally
    {
        while (stack.Count != 0)
        {
            stack.Pop().Dispose();
        }
    }
}

public static IEnumerable<T> SelectRecursive<T>(this IEnumerable<T> source, Func<T, IEnumerable<T>> getChildren)
{
    if (source == null) throw new ArgumentNullException(nameof(source));
    if (getChildren == null) return source;
    return SelectRecursiveIterator(source, getChildren);
}

有了这个，您可以迭代树中的所有节点，并返回所有匹配的节点：

With that in place, you can iterate all the nodes in your tree, and return either all matching nodes:

static IEnumerable<TreeNode> FindAllNodesByHeader(TreeView tree, string header)
{
    return tree.Items.Cast<TreeViewItem>().SelectRecursive(node => node.Items.Cast<TreeViewItem>()).Where(node => node.Header == header);
}

或只是第一个匹配的节点：

or just the first matching node:

static TreeNode FindFirstNodeByHeader(TreeView tree, string header)
{
    return tree.Items.Cast<TreeViewItem>().SelectRecursive(node => node.Items.Cast<TreeViewItem>()).FirstOrDefault(node => node.Header == header);
}

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