Python值传递给构造函数，变量仍然为空

Question

I created an instance of Wetter class and passed a number to the constructor. Variable zip stays empty. Why?

This is the value of url2 at the moment: "https://api.openweathermap.org/data/2.5/weather?zip=,DE&units=metric&appid=xxx"

zip= has no value.

I tried deleting the variable from the class, because I declared the variable as empty.

import requests
import json

class Wetter:
    key = "xxx" # API KEY von openweathermaps eintragen
    url = "https://api.openweathermap.org/data/2.5/weather?zip="
    parameters = ",DE&units=metric&appid=" + str(key)
    zip = ""
    url2 = "https://api.openweathermap.org/data/2.5/weather?zip=" + str(zip) + ",DE&units=metric&appid=" + str(key)
    data = ""
    json = ""

    def __init__(this, zip):
        this.zip = zip

    def printWeather(this):
        this.data = requests.get(this.url2)
        this.json = json.loads(this.data.text)
        print("Stadt: " + str(this.json["name"]) + "\nTemperatur: " + str(this.json["main"]["temp"]))

if __name__ == "__main__":
    zip = str(input("PLZ eingeben: "))
    obj = Wetter(zip)
    obj.printWeather()

I expect the variable to be filled with the delivered zip value.

Answer 1

You need to update url2 after this.zip was changed:

def __init__(this, zip):
    this.zip = zip
    this.url2 = "https://api.openweathermap.org/data/2.5/weather?zip=" + str(this.zip) + ",DE&units=metric&appid=" + str(this.key)

Answer 2

It's a simple mistake Instead of doing

    zip = ""

Try doing

    this.zip = ""