如何在python文件中正确保存信息

Question

我在 kivy 应用程序中保存和读取文件时遇到问题。由于某种原因，保存文件后会出现新空格。

我认为重点是“文本末尾带有 ” 读取为一行，但输入为两行字段，然后保存为两行文件，这成为一个问题。

我签署了代码中处理文件的位置。 请帮助我，因为我自己也不明白。

测试.py '''

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen


class Screeen(Screen):
    None
class Manager(ScreenManager):
    None



class appApp(App):


    def on_start(self):  # When the application starts, the file is read and the data is entered into the input fields
        with open("settings.txt", 'r') as f:
            self.a = f.readline()
            self.b = f.readline()
            self.c = f.readline()
            f.close()


            self.sm.get_screen("Screeen").ids.a.text = self.a
            self.sm.get_screen("Screeen").ids.b.text = self.b
            self.sm.get_screen("Screeen").ids.c.text = self.c


    def on_stop(self):   # after exiting the application, data from the input fields is saved to a file
        with open("settings.txt", "w") as f:
            f.write(self.sm.get_screen("Screeen").ids.a.text + "\n")
            f.write(self.sm.get_screen("Screeen").ids.b.text + "\n")
            f.write(self.sm.get_screen("Screeen").ids.c.text + "\n")


    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        # type-hint will help the IDE guide you to methods, etc.
        self.sm: ScreenManager = Builder.load_file("test.kv")


    def build(self):
        return self.sm



if __name__ == "__main__":
    appApp().run()

'''

测试.kv：

'''

Manager:
    Screeen:

<Screeen>:
    name: "Screeen"
    FloatLayout:
        size: root.width, root.height
        TextInput:
            id: a
            text: ""
            size_hint: (.25, .1)
            pos: root.width * 1 / 3 , root.height * 3 / 4

        TextInput:
            id: b
            text: ""
            size_hint: (.25, .1)
            pos: root.width * 1 / 3 , root.height * 2 / 4

        TextInput:
            id: c
            text: ""
            size_hint: (.25, .1)
            pos: root.width * 1 / 3 , root.height * 1 / 4

'''

并且settings.txt为空

Answer 1

readline() 将返回终止换行符。因此，您可以将 on_start() 函数重写如下：

def on_start(self):
    _ids = self.sm.get_screen("Screeen").ids
    with open("settings.txt") as f:
        for attr in "abc":
            _ids[attr].text = f.readline().rstrip()