# 正文

rapidjson与json有诸多不兼容，使用时需要注意。

两者输出的JSON格式有差异，json为了美观，在冒号和逗号之后默认加了空格。

rapidjson

```python
[yz@test-4 yz]$ python3
>>> import rapidjson as json
>>> s = '{"x": "123", "y": "456"}'
>>> r = json.loads(s)
>>> j = json.dumps(r, indent=None, ensure_ascii=False)
>>> print(j)
{"x":"123","y":"456"}
```

json

```python
[yz@test-4 yz]$ python3
>>> import json
>>> s = '{"x": "123", "y": "456"}'
>>> r = json.loads(s)
>>> j = json.dumps(r, indent=None, ensure_ascii=False)
>>> print(j)
{"x": "123", "y": "456"}
```

json可以使用`separators`控制是否加空格，但是，rapidjson没有这个参数。

```python
[yz@test-4 yz]$ python3
>>> import json
>>> s = '{"x": "123", "y": "456"}'
>>> r = json.loads(s)
>>> j = json.dumps(r, indent=None, ensure_ascii=False)
>>> print(j)
{"x": "123", "y": "456"}
>>> j = json.dumps(r, indent=None, ensure_ascii=False, separators=(',',':'))
>>> print(j)
{"x":"123","y":"456"}
>>> j = json.dumps(r, indent=None, ensure_ascii=False, separators=(', ',': '))
>>> print(j)
{"x": "123", "y": "456"}
```

`rapidjson.dumps`没有`separators`参数：

```python
[yz@test-4 yz]$ python3
>>> import rapidjson as json
>>> s = '{"x": "123", "y": "456"}'
>>> r = json.loads(s)
>>> j = json.dumps(r, indent=None, ensure_ascii=False, separators=(', ',': '))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'separators' is an invalid keyword argument for rapidjson.dumps()
```

# 参考

* [Python去除json.dumps()生成的空格](https://blog.csdn.net/lly1122334/article/details/105120034)
* [json.dumps](https://docs.python.org/3/library/json.html#json.dumps)