0

我有这个代码：

def getExchangeRates():
    rates = []
    response = urlopen('my_key')
    data = response.read()
    rdata = json.loads(data.decode(), parse_float=float) 

    rates.append( rdata['rates']['USD'] )
    rates.append( rdata['rates']['GBP'] )
    rates.append( rdata['rates']['HKD'] )
    rates.append( rdata['rates']['AUD'] )
    return rates

此代码正在运行，但现在我收到以下错误：

Traceback (most recent call last):
File "/home/kristian/.virtualenvs/usio_flask/lib/python3.4/site-packages/flask/app.py", line 2292, in wsgi_app
response = self.full_dispatch_request()
File "/home/kristian/.virtualenvs/usio_flask/lib/python3.4/site-packages/flask/app.py", line 1815, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/home/kristian/.virtualenvs/usio_flask/lib/python3.4/site-packages/flask/app.py", line 1718, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/home/kristian/.virtualenvs/usio_flask/lib/python3.4/site-packages/flask/_compat.py", line 35, in reraise
raise value
File "/home/kristian/.virtualenvs/usio_flask/lib/python3.4/site-packages/flask/app.py", line 1813, in full_dispatch_request
rv = self.dispatch_request()
File "/home/kristian/.virtualenvs/usio_flask/lib/python3.4/site-packages/flask/app.py", line 1799, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "app/app.py", line 30, in index
rates = getExchangeRates()
File "app/app.py", line 22, in getExchangeRates
rates.append( rdata['rates']['USD'] )
KeyError: 'rates'

奇怪的是，rates这里正在初始化：

rates = []

有任何想法吗？

4

2 回答 2

2

这KeyError是因为rates不是 rdata 中的键。在字典上查找键时，捕获KeyError或使用它总是一个好主意，get它允许您提供默认值以防找不到键。下面的代码说明了这两种方法：

rates_from_rdata = rdata.get('rates', {})
for rate_symbol in ['USD', 'GBP', 'HKD', 'AUD']:
    try:
        rates.append(rates_from_rdata[rate_symbol])
    except KeyError:
        print ('rate for {} not found in rdata'.format(rate_symbol))
        pass
于 2018-08-15T19:48:07.720 回答
1

执行以下操作

res = requests.get("http://data.fixer.io/api/latest?access_key=0cf7e4582cfe4e7de960de93c6c4bf9a")
data=res.json()
print(data)

如果字典中有单引号中的费率，则使用单引号（您在做什么），否则如果“费率”在双引号中，则在附加时使用双引号。此外，请检查您的订阅计划，如果它是免费的，它不支持美元。

于 2019-07-05T10:21:46.203 回答