Question

I am working on a project that requires variables to be saved in a text file and then turned back into variables. For example, a text file containing

var = "123abc"

would be imported, and the variable and it's contents imported into the code, allowing me to read what the variable var contained. This works great using this code:

def get_save(filename):
result = {}
with open(filename) as f:
    for line in f:
        try:
            line = line.split(' = ',1)
            result[line[0]] = ast.literal_eval(line[1].strip())
        except:
            pass
return result

globals().update(get_save('SAVEFILE.TXT'))

However, I want to do something a little more complex. I would like to be able to create objects within this text file. Here is an example class:

class object():
    def __intit__(self, var, var2):
        self.var = var
        self.var2 = var2

I would then like to be able to do this within my text file:

ob = object("abc", 123)

or:

obs = [object("def", 456), object("ghi", 789)]

and have that imported into my code, ready to be played with. I can think of no way of doing this, any help would be much appreciated!

EDIT: I would like the text file to be easily editable and readable

Thanks

Answer 1

我相信您要找的是pickle或json图书馆两者都可以将整个python对象保存到文件中，并在以后加载相同的对象用法的基本示例：

import pickle

target_object = {some_value:3, other_value:4}
target_file = open("1.txt", "w")
pickle.dump(target_object, target_file)

然后加载：

fl = open("1.txt", "r")
obj = pickle.load(fl)

重要的一点是，正如文档所说，pickle的设计并不安全，因此不要加载用户上传的随机文件等。

但是，腌制文件不易编辑。我发现使用json设置文件更加舒适，因为它们可以通过简单的文本编辑器轻松编辑。这的工作原理大致相同：

json.dump()转储到文件中，json.load从文件加载。

但是json不能轻易编码任何对象。它最适合存储dicts 如果您需要更复杂的对象并保持文件可读性，则可以在对象上实现serialize和deserialize方法，基本上可以将它们迁移到dict和从dict迁移。这是一个（不完美）的例子：

class SomeObject(object):
    def __init__(self, x, y, data=None):
        if data:
            self.deserialize(data)
        else:
            self.x = x
            self.y = y
    def serialize(self):
        return dict(x=self.x, y=self.y)
    def deserialize(self, data):
        self.x = data['x']
        self.y = data['y']

Answer 2

您可以使用pickle将完整的对象存储到文件中。

import pickle

class Holiday():
    def __init__(self):
        self.holiday = True
        self.away = ''

    def set_away(self, holiday):
        if holiday:
            self.away = "Two weeks"

    def say_away(self):
        print(self.away)

obj = Holiday()
obj.set_away(1)

pickle.dump(obj, open('holiday.save', 'wb'))

recovered_obj = pickle.load( open('holiday.save', 'rb'))

recovered_obj.say_away()

Define object from text file

2 个答案: