Return 词典文本文件列表中最大字段的行 Python？

Question

我正在编写 Python 脚本。我需要 return 包含文本文件中最大 'uid' 字段的行。例如，在下面的文本文件示例中：

{
    "uid": 683,
    "user_id": "2",
    "timestamp": datetime.datetime(2020, 5, 17, 16, 39, 54),
    "status": 1,
    "punch": 0,
}, {
    "uid": 684,
    "user_id": "4",
    "timestamp": datetime.datetime(2020, 5, 17, 16, 41, 20),
    "status": 1,
    "punch": 0,
}

Return 文本文件例如：

{
    "uid": 684,
    "user_id": "4",
    "timestamp": datetime.datetime(2020, 5, 17, 16, 41, 20),
    "status": 1,
    "punch": 0,
}

Answer 1

这是我的解决方案，我没有读取文本文件，而是使用了来自字符串变量 text.

的文本

最终结果（具有最大 uid 的条目）包含在 max_entry 变量中。我将此结果作为字符串写入文本文件 result.txt.

Try it online!

import datetime

text = """
{
    "uid": 683,
    "user_id": "2",
    "timestamp": datetime.datetime(2020, 5, 17, 16, 39, 54),
    "status": 1,
    "punch": 0,
}, {
    "uid": 684,
    "user_id": "4",
    "timestamp": datetime.datetime(2020, 5, 17, 16, 41, 20),
    "status": 1,
    "punch": 0,
}
"""

data = eval('[' + text + ']')
max_entry = max(data, key = lambda e: e['uid'])
print(max_entry)

with open('result.txt', 'w', encoding = 'utf-8') as f:
    f.write(str(max_entry))

输出：

{'uid': 684, 'user_id': '4', 'timestamp': datetime.datetime(2020, 5, 17, 16, 41, 20), 'status': 1, 'punch': 0}

Answer 2

你表明你的“文本文件”是一个字典列表。所以你可以这样做：

import datetime

text_file = {
    "uid": 683,
    "user_id": "2",
    "timestamp": datetime.datetime(2020, 5, 17, 16, 39, 54),
    "status": 1,
    "punch": 0,
}, {
    "uid": 684,
    "user_id": "4",
    "timestamp": datetime.datetime(2020, 5, 17, 16, 41, 20),
    "status": 1,
    "punch": 0,
}

def return_highest_ui_line(text_file):
    temp = []
    for i,sub_dict in enumerate(text_file):
        temp.append([sub_dict['uid'],i])
    return text_file[sorted(temp)[-1][1]]


return_highest_ui_line(text_file)

output:
{'uid': 684,
 'user_id': '4',
 'timestamp': datetime.datetime(2020, 5, 17, 16, 41, 20),
 'status': 1,
 'punch': 0}

Answer 3

我通过以下方式解决了这个问题：

import datetime
with open('C:/Users/UI UX/Desktop/newss.txt') as infile:
    for line in infile:
        data = eval('[' + line + ']')
        max_entry = max(data, key=lambda e: e['uid'])
        print(max_entry)

        with open('result.txt', 'w', encoding='utf-8') as f:
            f.write(str(max_entry))

Return 词典文本文件列表中最大字段的行 Python？

Return line of largest field in list of dictionaries text file with Python?

python

python-3.x

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