How to use django template dot notation inside a for loop

问题

I am trying to retrieve the value of a dictionary key and display that on the page in a Django template:

{% for dictkey in keys %}
    <p> {{ mydict.dictkey }} </p>
{% endfor %}

(let's say 'keys' and 'mydict' have been passed into the template in the Context)

Django renders the page but without the dictionary contents ("Invalid template variable")

I assume the problem is that it is trying to do mydict['dictkey'] instead of mydict[actual key IN the variable dictkey]? How does one "escape" this behavior?

Thanks!

UPDATE: Based on the answers received, I need to add that I'm actually looking specifically for how to achieve a key lookup inside a for loop. This is more representative of my actual code:

{% for key, value in mydict1.items %}
    <p> {{ mydict2.key }} </p>
{% endfor %}

Basically, I have two dictionaries that share the same keys, so I can't do the items() trick for the second one.

回答1:

See this answer to a (possibly duplicate) related question.

It creates a custom filter that, when applied to a dictionary with a key as it's argument, does the lookup on the dictionary using the key and returns the result.

Code:

@register.filter
def lookup(d, key):
    if key not in d:
        return None
    return d[key]

Usage:

{% for dictkey in dict1.keys %}
    <p> {{ dict2|lookup:dictkey }} </p>
{% endfor %}

Registering the filter is covered in the documentation.

I find it sad that this sort of thing isn't built in.

回答2:

From http://docs.djangoproject.com/en/dev/ref/templates/builtins/#for

This can also be useful if you need to access the items in a dictionary. For example, if your context contained a dictionary data, the following would display the keys and values of the dictionary:

{% for key, value in data.items %}
    {{ key }}: {{ value }}
{% endfor %}

The trick is that you need to call dict.items() to get the (key, value) pair.

回答3:

See the docs: http://docs.djangoproject.com/en/dev/ref/templates/builtins/#for

{% for key, value in data.items %}
    {{ key }}: {{ value }}
{% endfor %}

来源：https://stackoverflow.com/questions/4363032/how-to-use-django-template-dot-notation-inside-a-for-loop

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python

django

django-templates