TreeView獲取選定節點問題

Question

嘗試獲取樹視圖中選定的父節點標題和子節點標題，但出現無法將字符串轉換爲TreeViewItem的錯誤。

private void tvSQLTasks_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e) 
    { 
     //error is here 
     TreeViewItem child = (TreeViewItem)tvSQLTasks.SelectedItem; 

     if (child.Parent is TreeViewItem) 
     { 
      TreeViewItem parent = (TreeViewItem)child.Parent; 

      SQLTask _task = SQLTasks.Where(t => t._rootNode.Equals(parent.Header.ToString()) && t._childNode.Equals(child.Header.ToString())).FirstOrDefault(); 

      if (_task != null) 
      { 
       txtTaskDescription.Text = _task._taskDescription; 
      } 
     } 
    } 

下面的是我如何添加節點

 private void AddRootNode(string _nodeName) 
    { 
     tvSQLTasks.Items.Add(new TreeViewItem() { Header = _nodeName }); 
    } 

    private void AddChildNode(string _rootNode, string _childeNode) 
    { 
     foreach (TreeViewItem node in tvSQLTasks.Items) 
     { 
      if (node.Header.Equals(_rootNode)) 
      { 
       (node as TreeViewItem).Items.Add(_childeNode); 
      } 
     } 
    } 

Answer 1

這似乎是問題行：

(node as TreeViewItem).Items.Add(_childeNode); 

嘗試將其更改爲：

node.Items.Add(new TreeViewItem() { Header = _childeNode});