62 lines
1.2 KiB
Markdown
62 lines
1.2 KiB
Markdown
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# Python 字典快速指南
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> 原文：<https://www.pythonforbeginners.com/dictionary/python-dictionary-quick-guide>
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如题，这是一本 Python 字典快速指南。
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请查看[字典教程](https://www.pythonforbeginners.com/basics/dictionary)了解更多关于字典的文章。
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```py
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# key/value pairs declaration
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dict = {
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‘key1′:’value1′,
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‘key2′:’value2′,
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‘key3′:’value3′
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}
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#Get all keys
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dict.keys()
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#Get all values
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dict.values()
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#Modifying
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dict['key2'] = ‘value8′
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#Accessing
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print dict['key1']
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# prints ‘value2′
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print dict['key2']
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# empty declaration + assignment of key-value pair
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emptyDict = {}
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emptyDict['key4']=’value4′
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# looping through dictionaries (keys and values)
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for key in dict:
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print dict[key]
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# sorting keys and accessing their value in order
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keys = dict.keys()
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keys.sort()
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for key in keys:
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print dict[key]
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# looping their values directory (not in order)
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for value in dict.values():
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print value
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# getting both the keys and values at once
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for key,value in dict.items():
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print “%s=%s” % (key,value)
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# deleting an entry
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del dict['key2']
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# delete all entries in a dictionary
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dict.clear()
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# size of the dictionary
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len(dict)
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```
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