关闭程序后如何保存数据？

Posted 2023-05-07

【中文标题】关闭程序后如何保存数据？

【英文标题】：How could I save data after closing my program?

【发布时间】：2015-02-22 18:53:24

【问题描述】：

我目前正在使用字典制作电话簿目录。关闭程序后，我不知道有什么方法可以保存信息。我需要保存变量信息，以便以后添加更多并打印。

    Information="Police":911
    def NewEntry():
        Name=raw_input("What is the targets name?")
        Number=raw_input("What is the target's number?")
        Number=int(Number)
        Information[Name]=Number

    NewEntry()
    print Information

编辑：我现在正在使用 Pickle 模块，这是我当前的代码，但它不起作用：

     import pickle
     Information="Police":911
     pickle.dump(Information,open("save.p","wb"))
      def NewEntry():
         Name=raw_input("What is the targets name?")
         Number=raw_input("What is the target's number?")
         Number=int(Number)
         Information[Name]=Number
    Information=pickle.load(open("save.p","rb"))
    NewEntry()
    pickle.dump(Information,open("save.p","wb"))
    print Information

【参考方案1】：

您可以将文本文件作为字符串写入，然后读取解析为字典：

Write

with open('info.txt', 'w') as f:
    f.write(str(your_dict))

Read

import ast

with open('info.txt', 'r') as f:
    your_dict = ast.literal_eval(f.read())

【参考方案2】：

您可以使用Pickle 模块：

 import pickle

 # Save a dictionary into a pickle file.    
 favorite_color =  "lion": "yellow", "kitty": "red" 
 pickle.dump( favorite_color, open( "save.p", "wb" ) )

或者：

 # Load the dictionary back from the pickle file.
 favorite_color = pickle.load( open( "save.p", "rb" ) )

【参考方案3】：

Pickle 有效，但读取腌制对象存在一些潜在的安全风险。

另一个有用的技术是创建一个 phonebook.ini 文件并使用 python 的 configparser 处理它。这使您能够在文本编辑器中编辑 ini 文件并轻松添加条目。

** 我在此解决方案中使用 Python 3 的新 f 字符串，并将“信息”重命名为“电话簿”以遵守标准变量命名约定

您可能希望为强大的解决方案添加一些错误处理，但这说明了您的观点：

import configparser

INI_FN = 'phonebook.ini'


def ini_file_create(phonebook):
    ''' Create and populate the program's .ini file'''
    with open(INI_FN, 'w') as f:
        # write useful readable info at the top of the ini file
        f.write(f'# This INI file saves phonebook entries\n')
        f.write(f'# New numbers can be added under [PHONEBOOK]\n#\n')
        f.write(f'# ONLY EDIT WITH "Notepad" SINCE THIS IS A RAW TEXT FILE!\n\n\n')
        f.write(f"# Maps the name to a phone number\n")
        f.write(f'[PHONEBOOK]\n')
        # save all the phonebook entries
        for entry, number in phonebook.items():
            f.write(f'entry = number\n')
        f.close()


def ini_file_read():
    ''' Read the saved phonebook from INI_FN .ini file'''
    # process the ini file and setup all mappings for parsing the bank CSV file
    config = configparser.ConfigParser()
    config.read(INI_FN)
    phonebook = dict()
    for entry in config['PHONEBOOK']:
        phonebook[entry] = config['PHONEBOOK'][entry]
    return phonebook

# populate the phonebook with some example numbers
phonebook = "Police": 911
phonebook['Doc'] = 554

# example call to save the phonebook
ini_file_create(phonebook)

# example call to read the previously saved phonebook
phonebook = ini_file_read()

这是创建的phonebook.ini文件的内容

# This INI file saves phonebook entries
# New numbers can be added under [PHONEBOOK]
#
# ONLY EDIT WITH "Notepad" SINCE THIS IS A RAW TEXT FILE!


# Maps the name to a phone number
[PHONEBOOK]
Police = 911
Doc = 554