您可以只设置：

treeView1.ItemsSource = coldDrinks;

不过，我怀疑这里使用一个TreeView的。你显然呈现出平整，无分层数据，因此没有理由用一个TreeView。

However, I question the use of a TreeView here. You're obviously showing flat, non-hierarchical data, so there is no reason to use a TreeView.

为什么不直接使用一个ListView或列表框？

Why not just use a ListView or ListBox?