Module easygui :: Class EgStore |
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# Class EgStore

source code

A class to support persistent storage.

You can use EgStore to support the storage and retrieval of user settings for an EasyGui application.

# Example A #----------------------------------------------------------------------- # define a class named Settings as a subclass of EgStore #----------------------------------------------------------------------- class Settings(EgStore): :

           def __init__(self, filename):  # filename is required
                   #-------------------------------------------------
                   # Specify default/initial values for variables that
                   # this particular application wants to remember.
                   #-------------------------------------------------
                   self.userId = ""
                   self.targetServer = ""

                   #-------------------------------------------------
                   # For subclasses of EgStore, these must be
                   # the last two statements in  __init__
                   #-------------------------------------------------
                   self.filename = filename  # this is required
                   self.restore()            # restore values from the storage file if possible

# Example B #----------------------------------------------------------------------- # create settings, a persistent Settings object #----------------------------------------------------------------------- settingsFile = "myApp_settings.txt" settings = Settings(settingsFile)

user = "obama_barak" server = "whitehouse1" settings.userId = user settings.targetServer = server settings.store() # persist the settings

# run code that gets a new value for userId, and persist the settings user = "biden_joe" settings.userId = user settings.store()

# Example C #----------------------------------------------------------------------- # recover the Settings instance, change an attribute, and store it again. #----------------------------------------------------------------------- settings = Settings(settingsFile) settings.userId = "vanrossum_g" settings.store()

Instance Methods | [hide private]
__init__(self, filename) | source code
restore(self) Set the values of whatever attributes are recoverable from the pickle file. | source code
store(self) Save the attributes of the EgStore object to a pickle file. | source code
kill(self) Delete my persistent file (i.e. | source code
__str__(self) return my contents as a string in an easy-to-read format. | source code

Method Details | [hide private]

### restore(self) | source code
Set the values of whatever attributes are recoverable from the pickle file. Populate the attributes (the __dict__) of the EgStore object from the attributes (the __dict__) of the pickled object. If the pickled object has attributes that have been initialized in the EgStore object, then those attributes of the EgStore object will be replaced by the values of the corresponding attributes in the pickled object. If the pickled object is missing some attributes that have been initialized in the EgStore object, then those attributes of the EgStore object will retain the values that they were initialized with. If the pickled object has some attributes that were not initialized in the EgStore object, then those attributes will be ignored. IN SUMMARY: After the recover() operation, the EgStore object will have all, and only, the attributes that it had when it was initialized. Where possible, those attributes will have values recovered from the pickled object.

### store(self) | source code
Save the attributes of the EgStore object to a pickle file. Note that if the directory for the pickle file does not already exist, the store operation will fail.

### kill(self) | source code
Delete my persistent file (i.e. pickle file), if it exists.