如何在循环中只格式化项目的数量

Question

我在线阅读了一个文件并将其转换为JSON。我已经得到了工作结果，但想要格式化数字(23456876到23,456,875和345653到345,653)

data_file = [{"name":"python", "downloads":23456876, "version": "3.4.2", "version_downloads": 345653 }]

我写了代码来获取值，但如果我在for k in key中使用try except语句。它不能转换，我也用了另一种方法，但得到了cannot convert automatic fields to mamual formatting or something

titles = ["name", "downloads", "version", "Latest downloads"]
key = ["name", "downloads", "version", "version_downloads"]
i = 0
while i < len(data_file):
    results = []
    for k in key: 
        print("{}: {}".format(titles[key.index(k)], data_file[i][k]))
    print()
    i+=1

结果现在看起来像这样:

name: python
downloads: 23456876
latest version: 3.4.2
Latest downloads: 345653

如何打印downloads为:

downloads: 2,345,676
Latest downloads: 345653

Answer 1

不知道你在做什么索引，但你可以使用isinstance检查int并进行格式化，如果它是:

data_file = [{"name":"python", "downloads":23456876, "version": "3.4.2", "version_downloads": 345653 }]

titles = ["name", "downloads", "version", "Latest downloads"]
key = ["name", "downloads", "version", "version_downloads"]
for  d in data_file:
    for k in key:
        val = d[k]
        if isinstance(val, int):
            val = "{:,}".format(val)
        print("{}: {}".format(titles[key.index(k)], val))

输出:

name: python
downloads: 23,456,876
version: 3.4.2
Latest downloads: 345,653

我将使用字典来映射名称并进行查找，而不是索引:

titles = ["name", "downloads", "version", "Latest downloads"]
key = ["name", "downloads", "version", "version_downloads"]
match = dict(zip(key,titles))
for  d in data_file:
    for k in key:
        val = d[k]
        if isinstance(val, int):
            val = "{:,}".format(val)
        print("{}: {}".format(match[k], val))

输出:

name: python
downloads: 23,456,876
version: 3.4.2
Latest downloads: 345,653

如果唯一的区别是"version_downloads"，则使用If进行检查可能更简单。