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Try this
import json
with open('filename.txt', 'r') as f:
array = json.load(f)
print (array)
Based on reading over the documentation again, it appears you need to either change the third line to
json_data = json.loads(text)
or remove the line
text = json_file.read()
since read() causes the file's index to reach the end of the file. (I suppose, alternatively, you can reset the index of the file).
The json.load() method (without "s" in "load") can read a file directly:
import json
with open('strings.json') as f:
d = json.load(f)
print(d)
You were using the json.loads() method, which is used for string arguments only.
The error you get with json.loads is a totally different problem. In that case, there is some invalid JSON content in that file. For that, I would recommend running the file through a JSON validator.
There are also solutions for fixing JSON like for example How do I automatically fix an invalid JSON string?.
Here is a copy of code which works fine for me,
import json
with open("test.json") as json_file:
json_data = json.load(json_file)
print(json_data)
with the data
{
"a": [1,3,"asdf",true],
"b": {
"Hello": "world"
}
}
You may want to wrap your json.load line with a try catch, because invalid JSON will cause a stacktrace error message.
data is a Python dictionary. It needs to be encoded as JSON before writing.
Use this for maximum compatibility (Python 2 and 3):
import json
with open('data.json', 'w') as f:
json.dump(data, f)
On a modern system (i.e. Python 3 and UTF-8 support), you can write a nicer file using:
import json
with open('data.json', 'w', encoding='utf-8') as f:
json.dump(data, f, ensure_ascii=False, indent=4)
See json documentation.
To get utf8-encoded file as opposed to ascii-encoded in the accepted answer for Python 2 use:
import io, json
with io.open('data.txt', 'w', encoding='utf-8') as f:
f.write(json.dumps(data, ensure_ascii=False))
The code is simpler in Python 3:
import json
with open('data.txt', 'w') as f:
json.dump(data, f, ensure_ascii=False)
On Windows, the encoding='utf-8' argument to open is still necessary.
To avoid storing an encoded copy of the data in memory (result of dumps) and to output utf8-encoded bytestrings in both Python 2 and 3, use:
import json, codecs
with open('data.txt', 'wb') as f:
json.dump(data, codecs.getwriter('utf-8')(f), ensure_ascii=False)
The codecs.getwriter call is redundant in Python 3 but required for Python 2
Readability and size:
The use of ensure_ascii=False gives better readability and smaller size:
>>> json.dumps({'price': '€10'})
'{"price": "\\u20ac10"}'
>>> json.dumps({'price': '€10'}, ensure_ascii=False)
'{"price": "€10"}'
>>> len(json.dumps({'абвгд': 1}))
37
>>> len(json.dumps({'абвгд': 1}, ensure_ascii=False).encode('utf8'))
17
Further improve readability by adding flags indent=4, sort_keys=True (as suggested by dinos66) to arguments of dump or dumps. This way you'll get a nicely indented sorted structure in the json file at the cost of a slightly larger file size.