Python3基础 dict get 在查询不存在的键时，返回指定的内容

Posted 2021-01-08 xingchuxin

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•                    python : 3.7.0
•                           OS : Ubuntu 18.04.1 LTS
  
•                          IDE : PyCharm 2018.2.4
•                      conda : 4.5.11
•            type setting : Markdown

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code

"""
@Author : 行初心
@Date   : 18-9-23
@Blog   : www.cnblogs.com/xingchuxin
@GitHub : github.com/GratefulHeartCoder
"""


def main():
    my_dict = {‘子‘: ‘鼠‘, ‘丑‘: ‘牛‘, ‘寅‘: ‘虎‘, ‘卯‘: ‘兔‘,
               ‘辰‘: ‘龙‘, ‘巳‘: ‘蛇‘, ‘午‘: ‘马‘, ‘未‘: ‘羊‘,
               ‘申‘: ‘猴‘, ‘酉‘: ‘鸡‘, ‘戌‘: ‘狗‘, ‘亥‘: ‘猪‘}

    print(my_dict.get(‘子‘, ‘你所查询的键不存在‘))

    print(my_dict.get(‘行‘, ‘你所查询的键不存在‘))

    # 不设置参数的话，返回None
    print(my_dict.get(‘行‘))


if __name__ == ‘__main__‘:
    main()

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result

/home/coder/anaconda3/envs/py37/bin/python /home/coder/PycharmProjects/DataStructure/demo.py
鼠
你所查询的键不存在
None

Process finished with exit code 0

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resource

• [文档] https://docs.python.org/3/
• [规范] https://www.python.org/dev/peps/pep-0008/
• [规范] https://zh-google-styleguide.readthedocs.io/en/latest/google-python-styleguide/python_language_rules/
• [源码] https://www.python.org/downloads/source/
• [ PEP ] https://www.python.org/dev/peps/
• [平台] https://www.cnblogs.com/

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