Changing instance variables from a method in a class

Question

I've made a class with some variables being set in the ___init____ and I want to be able to change these variables from methods in that class ie.

class example_class:

    def __init__(self, variable):
        self.thing = 'variable'

    def example_method(self):
        self.thing = 'changed text'

    def different_method(self):
        print(self.thing)

So before calling "example_method" the value of self.thing is the string 'variable' and then after calling the method "example_method" self.thing now equals 'changed text'. This must be possible but I don't understand how to do it

What problem are you actually seeing with your implementation? — khelwood
– khelwood, Commented Dec 7, 2017 at 9:47
After running the method example_method the value of self.thing is still the original string 'variable' it hasn't changed to 'changed text' — tombat7112
– tombat7112, Commented Dec 7, 2017 at 10:11

Paradisee · Accepted Answer · 2017-12-07 09:50:55Z

1

You must call the method you've defined into the class to happen.

class example_class:

    def __init__(self, variable):
        self.thing = 'variable'
        self.example_method()

    def example_method(self):
        self.thing = 'changed text'

    def different_method(self):

In this way, when you get/create an instance of the class "example_class", the method "example_method" will be called in the constructor.

You could also do something like:

if __name__ == '__main__':
    my_class = example_class()
    my_class.example_method()

answered Dec 7, 2017 at 9:50

Paradisee

298 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

tombat7112 Over a year ago

I realise I haven't but the code in my post but I do call the method I just don't want to call it in the init. I want to construct the instance of the class and then later be able to call "example_method" to change the variable self.thing

Paradisee Over a year ago

you don't need to call the method inside the init method if you won't. But as i said in my previous post, you want something similar to the last 3 rows of code. You need an instance of that class and after you can easily call the method you want from it.

tombat7112 Over a year ago

Yeah I have created an instance of the class and then call the method but the string still doesn't change

Paradisee Over a year ago

Then you're doing something wrong, please post the code.

Collectives™ on Stack Overflow

Changing instance variables from a method in a class

1 Answer 1

4 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Related