如何在Python中将多个JSON文件合并为一个文件

Question

我希望能够在Python中将多个JSON文件合并成一个文件。 我想做的事情是，如果有几个.json文件：

# temp1.json
[{'num':'1', 'item':'smartphone','data':'2019-01-01'},
{'num':'2', 'item':'smartphone','data':'2019-01-02'},
{'num':'3', 'item':'smartphone','data':'2019-01-03'},
{'num':'4', 'item':'smartphone','data':'2019-01-04'}]

# temp2.json
[{'num':'5', 'item':'smartphone','data':'2019-01-05'},
{'num':'6', 'item':'smartphone','data':'2019-01-06'},
{'num':'7', 'item':'smartphone','data':'2019-01-07'}]

# temp3.json
[{'num':'8', 'item':'smartphone','data':'2019-01-08'},
{'num':'9', 'item':'smartphone','data':'2019-01-09'},
{'num':'10', 'item':'smartphone','data':'2019-01-10'},
{'num':'11', 'item':'smartphone','data':'2019-01-11'},
{'num':'12', 'item':'smartphone','data':'2019-01-12'}]

我想要的result.json文件应该长这样：

# result.json
[{'num':'1', 'item':'smartphone','data':'2019-01-01'},
{'num':'2', 'item':'smartphone','data':'2019-01-02'},
{'num':'3', 'item':'smartphone','data':'2019-01-03'},
{'num':'4', 'item':'smartphone','data':'2019-01-04'},
{'num':'5', 'item':'smartphone','data':'2019-01-05'},
{'num':'6', 'item':'smartphone','data':'2019-01-06'},
{'num':'7', 'item':'smartphone','data':'2019-01-07'},
{'num':'8', 'item':'smartphone','data':'2019-01-08'},
{'num':'9', 'item':'smartphone','data':'2019-01-09'},
{'num':'10', 'item':'smartphone','data':'2019-01-10'},
{'num':'11', 'item':'smartphone','data':'2019-01-11'},
{'num':'12', 'item':'smartphone','data':'2019-01-12'}]

我得到的result.json文件是：

# result.json
[[{'num':'1', 'item':'smartphone','data':'2019-01-01'},
{'num':'2', 'item':'smartphone','data':'2019-01-02'},
{'num':'3', 'item':'smartphone','data':'2019-01-03'},
{'num':'4', 'item':'smartphone','data':'2019-01-04'}],
[{'num':'5', 'item':'smartphone','data':'2019-01-05'},
{'num':'6', 'item':'smartphone','data':'2019-01-06'},
{'num':'7', 'item':'smartphone','data':'2019-01-07'}],
[{'num':'8', 'item':'smartphone','data':'2019-01-08'},
{'num':'9', 'item':'smartphone','data':'2019-01-09'},
{'num':'10', 'item':'smartphone','data':'2019-01-10'},
{'num':'11', 'item':'smartphone','data':'2019-01-11'},
{'num':'12', 'item':'smartphone','data':'2019-01-12'}]]

我使用了以下代码来合并这里的.json文件，并进行了微小的修改：

files=['my.json','files.json',...,'name.json']

def merge_JsonFiles(filename):
    result = list()
    for f1 in filename:
        with open(f1, 'r') as infile:
            result.append(json.load(infile))

    with open('counseling3.json', 'w') as output_file:
        json.dump(result, output_file)

merge_JsonFiles(files)

我已经阅读了几个相关的问题，但没有我需要的答案。有人能帮助我吗？

- wendykr

---

使用extend而不是append。 - Paul Rooney

@PaulRooney 谢谢 :) - wendykr

函数名称应为小写 - Michael

Answer 1

你应该使用extend而不是append。它会将传递的列表的项目添加到result而不是一个新列表中:

files=['my.json','files.json',...,'name.json']

def merge_JsonFiles(filename):
    result = list()
    for f1 in filename:
        with open(f1, 'r') as infile:
            result.extend(json.load(infile))

    with open('counseling3.json', 'w') as output_file:
        json.dump(result, output_file)

merge_JsonFiles(files)

- Akaisteph7

---

为什么它返回一个空列表？ - undefined

Answer 2

files=['my.json','files.json',...,'name.json']

with open('merged_file_name.json', "w") as outfile:
   outfile.write('{}'.format('\n'.join([open(f, "r").read() for f in files])))

- Abhi

---

回答问题时最好除了代码外还附带一些描述。 - keiv.fly

Answer 3

import json
import pandas as pd

with open('example1.json') as f1:               # open the file
    data1 = json.load(f1)

with open('example2.json') as f2:                # open the file       
    data2 = json.load(f2)
    
df1 = pd.DataFrame([data1])                      # Creating DataFrames
df2 = pd.DataFrame([data2])                      # Creating DataFrames

MergeJson = pd.concat([df1, df2], axis=1)         # Concat DataFrames

MergeJson.to_json("MergeJsonDemo.json")          # Writing Json

- Anjali Bhagat

---

从代码可读性的角度来看，我喜欢这个看起来多么简洁。 - Ryan Hart

参数：('ValueError'，ValueError（“DataFrame列在orient ='columns'时必须是唯一的。”）） - Dmitrij Holkin

Answer 4

如果目標是合併幾個JSON文件，請嘗試以下操作：

def combine_jsons():
    file_list = ['first.json', 'second.json',... ,'last.json']
    all_data_dict = {}
    for json_file in file_list:
       with open(json_file,'r+') as file:
           # First we load existing data into a dict.
           file_data = json.load(file)
       all_data_dict.update(file_data)
    with open('merged_data.json', "w") as outfile:# save to json file
        json.dump(all_data_dict, outfile)

如果必须是列表，请更改最后一行。

基于如下链接：如何在单个表达式中合并两个字典（取字典的并集）？

- YScharf

---

这会导致错误。 - lord stock

什么错误？缩进问题？已经修复！ - YScharf

Answer 5

def merge_files(self):
    res = list()
    for f1 in self.listDomainToMerge:
        item = json.load(open(f1, encoding="utf-8"))
        res.append(item)

    with open('../Configuration%s/configuration.json' % self.owner, 'w') as output:
        output.write(json.dumps(res, ensure_ascii=False, indent=2))

- Talex Maxim

Answer 6

还有另一种方法。只需将这些文件中的JSON文本加载为Python列表，然后将它们相加即可。代码如下。

# temp1.json
json_a = [{'num':'1', 'item':'smartphone','data':'2019-01-01'},
{'num':'2', 'item':'smartphone','data':'2019-01-02'},
{'num':'3', 'item':'smartphone','data':'2019-01-03'},
{'num':'4', 'item':'smartphone','data':'2019-01-04'}]

# temp2.json
json_b = [{'num':'5', 'item':'smartphone','data':'2019-01-05'},
{'num':'6', 'item':'smartphone','data':'2019-01-06'},
{'num':'7', 'item':'smartphone','data':'2019-01-07'}]

# temp3.json
json_c = [{'num':'8', 'item':'smartphone','data':'2019-01-08'},
{'num':'9', 'item':'smartphone','data':'2019-01-09'},
{'num':'10', 'item':'smartphone','data':'2019-01-10'},
{'num':'11', 'item':'smartphone','data':'2019-01-11'},
{'num':'12', 'item':'smartphone','data':'2019-01-12'}]

print(json_a + json_b + json_c)

输出：

[{'num': '1', 'item': 'smartphone', 'data': '2019-01-01'},
 {'num': '2', 'item': 'smartphone', 'data': '2019-01-02'},
 {'num': '3', 'item': 'smartphone', 'data': '2019-01-03'},
 {'num': '4', 'item': 'smartphone', 'data': '2019-01-04'},
 {'num': '5', 'item': 'smartphone', 'data': '2019-01-05'},
 {'num': '6', 'item': 'smartphone', 'data': '2019-01-06'},
 {'num': '7', 'item': 'smartphone', 'data': '2019-01-07'},
 {'num': '8', 'item': 'smartphone', 'data': '2019-01-08'},
 {'num': '9', 'item': 'smartphone', 'data': '2019-01-09'},
 {'num': '10', 'item': 'smartphone', 'data': '2019-01-10'},
 {'num': '11', 'item': 'smartphone', 'data': '2019-01-11'},
 {'num': '12', 'item': 'smartphone', 'data': '2019-01-12'}]

- Kay Zhang