如何在Windows窗体TreeView中按标签选择节点 [英] How to select a Node by Tag in Windows Forms TreeView

问题描述

我正在尝试通过标签选择一个节点。我已经搜寻了我能找到的，但仍然没有运气。我用它为我的 treeview

I'm trying to select a node by tag. I've searched what I can, but still with no luck. I used this to assign a tag to each node in my treeview

 foreach (DataRow dataRow in databaseFunc.dataTable.Rows)
 {
      TreeNode nodes = new TreeNode();
      nodes.Text = dataRow["LastName"].ToString().Trim() + ", " +
            dataRow["FirstName"].ToString().Trim();
      nodes.Tag = dataRow[0].ToString().Trim();
      treeView.Nodes.Add(nodes);
 }

我知道您可以使用以下方式选择节点：

I know you can select a node using:

 TreeNodeCollection nodeCollect = treeView.Nodes;
 treeView.SelectedNode = nodeCollect[index];

推荐答案

按标签查找

通过标记查找特别有用，当标记包含

Finding by Tag is useful specially when the Tag contains a complex object or you want to find based on a non-string key.

要能够在子节点上进行搜索，可以看一下在此处答复，并使用 Descendants 扩展方法来查找所有节点，包括子节点。然后，您可以通过 Tag 找到该节点。例如，如果标记包含产品，而您想根据其查找产品id ，您可以使用以下代码：

To be able to search on child nodes, you can take a look at the answer here and use Descendants extension method to find all nodes including child nodes. Then you can find the node by Tag. For example if the Tag contains a Product and you want to find the product based on its Id, you can use such code:

var result = tree.Descendants().Where(x=>((x.Tag as Product) != null) &&
                                     (x.Tag as Product).Id = someId).FirstOrDefault();

或者使用简单的字符串搜索键：

Or for a simple string search key:

var result = tree.Descendants().Where(x=>(x.Tag as string) == searchkey).FirstOrDefault();
if(result!=null)
    tree.SelectedNode = result;

如果只想在根节点之间搜索，请使用：

If you want to search just between root nodes, use:

var result = tree.Nodes.Cast<TreeNode>().Where(... the rest is like above.

按名称查找

您可以使用 查找节点集合的 方法，以根据其 名称 （不是文本）。当您要基于字符串键查找节点时，使用 Find 方法非常有用。为此，应设置创建节点时的节点名称。

You can use Find method of Nodes collection to find a node based on its Name(not the Text). Using Find method is useful when you want to find a node based on a string key. To do so, you should set the Name of node when you create the node.

var result = tree.Nodes.Find(searchKey , true).FirstOrDefault();
if(result !=null)
    tree.SelectedNode = result;

如果只想在根节点之间搜索，请使用：

If you want to search just between root nodes, use:

var result = tree.Nodes.Find(searchKey , false).FirstOrDefault();

注意

最后，可以使用 Tag 属性将复杂对象存储在 Tag 中，并在需要时将其取消装箱。对于字符串搜索键，最好使用Name 属性-a-node-by-tag-in-winforms-c-sharp＃comment56201370_34228617>评论。

As a conclusion you can use the Tag property to store a complex object in Tag and unbox it when you need. For string search keys, it's better to use Name property as said in the comments.

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