2. To
iterate through the child nodes and disregard those text nodes, you can check the node type.
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通过对子节点进行重申以及忽略这些子节点,你可以检验节点类型。
3. If you need to modify the list you are iterating over (for example, to duplicate selected items) you must
iterate over a copy.
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如果你想要修改你迭代的序列(例如,复制选择项),你可以迭代它的复本。