在pyhon

Question

我只想打印json文件

import json   
from country_codes import get_country_code

filename = 'gdp.json'

with open(filename) as f:
    pop_data = json.load(f)

cc_populations = {}

for pop_dict in pop_data:
    if pop_dict['Year'] == '1970':
        country_name = pop_dict['Country Name']
        population = int(float(pop_dict['Value']))
        code = get_country_code(country_name)
        if code:
            print(code + ": " + str(population))
        else:
            print('ERROR - ' + country_name)

json文件为here

运行时什么也没发生

Answer 1

JSON中的年份是整数。

将if pop_dict['Year'] == '1970':更改为if pop_dict['Year'] == 1970:

工作示例：

pop_data = [{"Country Code": "ARB", "Country Name": "Arab World", "Value": 25760683041.0857, "Year": 1968},{"Country Code": "ARB", "Country Name": "Arab World", "Value": 28434203615.4829, "Year": 1969},{"Country Code": "ARB", "Country Name": "Arab World", "Value": 31385499664.0672, "Year": 1970},]

import json

cc_populations = {}
for pop_dict in pop_data:
    if pop_dict['Year'] == 1970:
        country_name = pop_dict['Country Name']
        population = int(float(pop_dict['Value']))
        code = (country_name)
        if code:
            print(code + ": " + str(population))
        else:
            print('ERROR - ' + country_name)

输出：

  

阿拉伯世界：31385499664

旁注：Value已经是浮点数，因此无需强制转换float(pop_dict['Value'])。