目录

1. 从json文件读取数据

2. 将数据写入json文件

方法一：使用dump()函数

方法二：使用dumps()函数

完整代码

流程

json文件

Python 脚本

运行结果

控制台

base1.json

base2.json

---

 

1. 从json文件读取数据

 

使用load()函数获取json文件中的数据，并转换为Python的内置数据类型（列表或字典）。

下面自定义的函数read_json_file()实现了读取json文件数据的功能：

def read_json_file(url): """ Get the data for the json file. :param url: <str> json file path. :return: <dict/list> json file data. """ with open(url, "r") as json_file: data = json.load(json_file) json_file.close() return data

 

2. 将数据写入json文件

 

方法一：使用dump()函数

dump()函数可以将Python中的列表或字典写入到json文件中。可选参数indent指定缩进。

下面自定义的函数write_json_file_a()将数据写入到json文件中。

def write_json_file_a(data): """ Write Json file. :param data: <dict/list> data :return: <None> """ path = "base1.json" with open(path, "w") as json_file: json.dump(data, json_file, indent=6) json_file.close() print("Write %s success." % path) return

 

方法二：使用dumps()函数

dumps()函数跟dump()函数的用法有所不同。dumps()先将Python列表或字典转换成特定的字符串格式，再借用open()和write()函数将转换后的数据写入到json文件中。可选参数indent指定缩进。

下面自定义的函数write_json_file_b()将数据写入到json文件中。

def write_json_file_b(data): path = "base2.json" data = json.dumps(data, indent=4) open(path, "w").write(data) print("Write %s success." % path) return

 

 

完整代码

 

流程

代码从base.json读取数据，再将读取后的数据分别写入base1.json文件（6缩进）和base2.json文件（4缩进）。

 

json文件

待读取的base.json如下所示：

[ { "name": "iphone X", "manufacturer": "Apple", "type": "mobile phone" }, { "name": "HuaweiCloud", "manufacturer": "Huawei", "type": "Virtual cloud technology" }, { "name": "Android", "manufacturer": "Google", "type": "mobile machines system" } ]

 

Python 脚本

Python脚本在获取到json数据后打印在控制台上。然后分别使用两种写json文件的方式写入数据。

""" Note: Json actions demo. 1. Get Json data. 2. Write Json file. """ import json def read_json_file(url): """ Get the data for the json file. :param url: <str> json file path. :return: <dict/list> json file data. """ with open(url, "r") as json_file: data = json.load(json_file) json_file.close() return data def write_json_file_a(data): """ Write Json file. :param data: <dict/list> data :return: <None> """ path = "base1.json" with open(path, "w") as json_file: json.dump(data, json_file, indent=6) json_file.close() print("Write %s success." % path) return def write_json_file_b(data): path = "base2.json" data = json.dumps(data, indent=4) open(path, "w").write(data) print("Write %s success." % path) return if __name__ == "__main__": data = read_json_file("base.json") print("data: \n%s" % data) write_json_file_a(data) write_json_file_b(data)

 

 

运行结果

 

控制台

data: [{'name': 'iphone X', 'manufacturer': 'Apple', 'type': 'mobile phone'}, {'name': 'HuaweiCloud', 'manufacturer': 'Huawei', 'type': 'Virtual cloud technology'}, {'name': 'Android', 'manufacturer': 'Google', 'type': 'mobile machines system'}] Write base1.json success. Write base2.json success. Process finished with exit code 0

 

base1.json

base1文件中采用了6缩进写入。

[ { "name": "iphone X", "manufacturer": "Apple", "type": "mobile phone" }, { "name": "HuaweiCloud", "manufacturer": "Huawei", "type": "Virtual cloud technology" }, { "name": "Android", "manufacturer": "Google", "type": "mobile machines system" } ]

 

base2.json

base2文件中采用了4缩进写入。

[ { "name": "iphone X", "manufacturer": "Apple", "type": "mobile phone" }, { "name": "HuaweiCloud", "manufacturer": "Huawei", "type": "Virtual cloud technology" }, { "name": "Android", "manufacturer": "Google", "type": "mobile machines system" } ]