Python pandas to_json格式的索引

import pandas as pd

# 创建一个DataFrame对象
data = {'Name': ['Tom', 'Nick', 'John'],
        'Age': [28, 32, 25],
        'City': ['New York', 'Paris', 'London']}
df = pd.DataFrame(data)

# 将DataFrame转换为JSON格式的字符串，默认包含索引
json_str = df.to_json()
print(json_str)

# 将DataFrame转换为JSON格式的字符串，不包含索引
json_str_no_index = df.to_json(orient='records')
print(json_str_no_index)

# 将DataFrame转换为JSON格式的字符串，只包含值
json_str_values_only = df.to_json(orient='values')
print(json_str_values_only)

{"Name":{"0":"Tom","1":"Nick","2":"John"},"Age":{"0":28,"1":32,"2":25},"City":{"0":"New York","1":"Paris","2":"London"}}
[{"Name":"Tom","Age":28,"City":"New York"},{"Name":"Nick","Age":32,"City":"Paris"},{"Name":"John","Age":25,"City":"London"}]
[["Tom",28,"New York"],["Nick",32,"Paris"],["John",25,"London"]]