c# - c# 获取TreeView父节点列表

Question

如果我有一个 TreeView (myTreeview)，我如何获得所有作为父节点的节点的列表？即有孩子的节点

Answer 1

myTreeview.Nodes 将为您提供 MS 定义的根节点列表，这基本上意味着树根分支上的节点。

此代码将构建一个包含子节点的根节点列表：

    IList<TreeNode> nodesWithChildren = new List<TreeNode>();
    foreach( TreeNode node in myTreeview.Nodes )
        if( node.Nodes.Count > 0 ) nodesWithChildren.Add( node );

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更新：如果您希望 TreeView 中的所有节点都有一个子节点，而不管树有多深，那么请使用一些递归，例如

private static IList<TreeNode> BuildParentNodeList(TreeView treeView)
{
    IList<TreeNode> nodesWithChildren = new List<TreeNode>();

    foreach( TreeNode node in treeView.Nodes  )
        AddParentNodes(nodesWithChildren, node);

    return nodesWithChildren;
}

private static void AddParentNodes(IList<TreeNode> nodesWithChildren, TreeNode parentNode)
{
    if (parentNode.Nodes.Count > 0)
    {
        nodesWithChildren.Add( parentNode );
        foreach( TreeNode node in parentNode.Nodes )
            AddParentNodes( nodesWithChildren, node );
    }
}

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更新 2：只有 1 个 foreach 循环的递归方法：

private static IList<TreeNode> BuildParentNodeList(TreeView treeView)
{
    IList<TreeNode> nodesWithChildren = new List<TreeNode>();
    AddParentNodes( nodesWithChildren, treeView.Nodes );
    return nodesWithChildren;
}

private static void AddParentNodes(IList<TreeNode> nodesWithChildren, TreeNodeCollection parentNodes )
{
    foreach (TreeNode node in parentNodes)
    {
        if (node.Nodes.Count > 0)
        {
            nodesWithChildren.Add( node );
            AddParentNodes(nodesWithChildren, node.Nodes);
        }
    }
}

Answer 2

private void AddNonLeafNodes(List<TreeNode> nonLeafNodes, TreeNodeCollection nodes)
{
    foreach( TreeNode node in nodes )
    {
        if( node.Nodes.Count > 0 )
        {
            nonLeafNodes.Add(node);
            AddNonLeafNodes(nonLeafNodes,node.Nodes);
        }
    }
}

List<TreeNode> nonLeafNodes = new List<TreeNode>();
AddNonLeafNodes(nonLeafNodes,treeView1.Nodes);