Question

如果我在def get_context_data(self, **kwargs): coindex_btc_price = requests.get("http://api.coindesk.com/v1/bpi/currentprice.json") def get_queryset(self, **kwargs): coindex_btc_price = requests.get("http://api.coindesk.com/v1/bpi/currentprice.json")函数中设置了变量，有没有办法在'use strict'; var _module; if (true) { _module = 'lixo'; } else { _module = 'express'; } var A = require('' + _module);函数中访问该变量？

import numpy as np
from numpy import pi

from bokeh.client import push_session
from bokeh.driving import cosine
from bokeh.plotting import figure, curdoc

x = np.linspace(0, 4*pi, 80)
y = np.sin(x)

p = figure()
r1 = p.line([0, 4*pi], [-1, 1], color="firebrick")
r2 = p.line(x, y, color="navy", line_width=4)

# open a session to keep our local document in sync with server
session = push_session(curdoc())

@cosine(w=0.03)
def update(step):
    # updating a single column of the the *same length* is OK
    r2.data_source.data["y"] = y * step
    r2.glyph.line_alpha = 1 - 0.8 * abs(step)

curdoc().add_periodic_callback(update, 50)

session.show(p) # open the document in a browser

session.loop_until_closed() # run forever

我不想这样设置两次。

Answer 1

我会重构并创建一个保存值的实例变量：

def __init__(self):
    super(ClassName, self).__init__()
    self.coindex_btc_price = None

def get_coindex_price(self):
    if self.coindex_btc_price is None:
        self.coindex_btc_price = coindex_btc_price = requests.get("http://api.coindesk.com/v1/bpi/currentprice.json")
    return self.coindex_btc_price

def get_context_data(self, **kwargs):
    coindex_btc_price = self.get_coindex_price()

def get_queryset(self, **kwargs):
    coindex_btc_price = self.get_coindex_price()

Django Class Based View在get_queryset方法中访问get_context中的变量集

1 个答案: