Python Dictionary items() 函数用法

2023-09-17 22:23:30

dict.items()返回一个dictionary view object,该以键值对列表的形式提供字典元素的动态视图。此视图对象在字典更改时更改。

语法:

dict.items()

参数:

无参数。

返回值:

返回一个视图对象dict_items,该对象显示字典的键值对的列表。

下面的示例演示 dict.items() 方法。

romanNums = {'I':1,'II':2,'III':3,'IV':4}
dictview = romanNums.items()
print(dictview)

输出:

dict_items([('I', 1), ('II', 2), ('III', 3), ('IV', 4)])

下面的示例演示更新字典时视图对象如何更改。

romanNums = {'I':1,'II':2,'III':3,'IV':4}
dictview = romanNums.items()
print("Dictionary View Object: ", dictview)
romanNums['V'] = 5
print("Dictionary View Object after adding new element: ", dictview)

输出:

Dictionary View Object: dict_items([('I', 1), ('II', 2), ('III', 3), ('IV', 4)])
Dictionary View Object after adding new element:  dict_items([('I', 1), ('II', 2), ('III', 3), ('IV', 4), ('V', 5)])