如何打印字典中重复键的值？解决嵌套标题仅输出最后键值对问题

遍历字典列表时，发现NestedTabs中的重复Title键仅打印最后一组键值对（例如W3schools的嵌套Tabs仅输出JavaScript标题），如何实现打印字典中重复键的所有值？

使用的代码 #

def displayAllTabs(dict_items):
    for dict in dict_items:
        title = dict.get("Title")
        print(title)
        if "NestedTabs" in dict.keys():
            nestedTitle = dict["NestedTabs"]["Title"]
            print(f'\t{nestedTitle}')

原始字典列表 #

[
    {
        "index": 1,
        "Title": "SE Factory",
        "Url": "https://www.sefactory.io",
        "NestedTabs": {"Title": "UI", "Url": "https://www.sefactory.io/uix"},
    },
    {"index": 2, "Title": "Google", "Url": "https://www.google.com"},
    {
        "index": 3,
        "Title": "W3schools",
        "Url": "https://www.w3schools.com",
        "NestedTabs": {
            "Title": "Html",
            "Url": "https://www.w3schools.com/html/default.asp",
            "Title": "Css",
            "Url": "https://www.w3schools.com/css/default.asp",
            "Title": "JavaScript",
            "Url": "https://www.w3schools.com/js/default.asp",
        },
    },
]

Python的字典不支持重复键，当你在字典里定义多个同名键时，后面的键会直接覆盖前面的。所以W3schools的NestedTabs字典中，实际只保留了最后一组Title: JavaScript和对应的Url，前面的Html、Css条目都被覆盖了，自然无法打印出所有值。

1. 修正数据结构 #

把NestedTabs从单个字典改成字典列表，每个子项是包含Title和Url的独立字典，这样就能存储多个嵌套标签：

[
    {
        "index": 1,
        "Title": "SE Factory",
        "Url": "https://www.sefactory.io",
        "NestedTabs": [{"Title": "UI", "Url": "https://www.sefactory.io/uix"}],
    },
    {"index": 2, "Title": "Google", "Url": "https://www.google.com"},
    {
        "index": 3,
        "Title": "W3schools",
        "Url": "https://www.w3schools.com",
        "NestedTabs": [
            {"Title": "Html", "Url": "https://www.w3schools.com/html/default.asp"},
            {"Title": "Css", "Url": "https://www.w3schools.com/css/default.asp"},
            {"Title": "JavaScript", "Url": "https://www.w3schools.com/js/default.asp"},
        ],
    },
]

2. 修改遍历代码 #

修改displayAllTabs函数，循环遍历NestedTabs列表中的每个字典，打印所有Title：

def displayAllTabs(dict_items):
    for item in dict_items:
        title = item.get("Title")
        print(title)
        # 检查是否存在NestedTabs且是列表类型
        if "NestedTabs" in item and isinstance(item["NestedTabs"], list):
            for nested_tab in item["NestedTabs"]:
                nested_title = nested_tab.get("Title")
                print(f'\t{nested_title}')

运行结果 #

执行修改后的代码，会输出：

SE Factory
        UI
Google
W3schools
        Html
        Css
        JavaScript

内容的提问来源于stack exchange，提问作者Abbas Kanj