[Fixed]-Convert Python None to JavaScript null


If you’re using Python 2.6 or later, you can use the built-in json module:

>>> import json
>>> json.dumps([1, 2, 3, None, 4])
'[1, 2, 3, null, 4]'

See http://docs.python.org/library/json.html


When I tried the accepted solution json.dumps() returned NaN values rather than the null JavaScript is looking for. Therefore I found another solution that does not use json or simplejson packages. The following solution uses type checking of None in Django. The solution that inspired me can be found here.

I used it in my code as follows to populate a Javascript array correctly:

{% for val in data %}
     {% if val is none %}
     {% else %}
         {{ val }},
     {% endif %}
{% endfor %}

The none object in Django will check the None value offered by python. It doesn’t seem to correctly handle np.NaN objects though.

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