Python jinja2 - 如何在 if 语句中放置一个块？
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jinja2 - how to put a block in an if statement?
提问by Taxellool
I am trying to use an ifto determine which block should fill my {% block content %}.
我正在尝试使用 anif来确定哪个块应该填充我的{% block content %}.
I have a base.htmlwhich has a default {% block content %}and this template is extending base.html. So I tried this:
我有一个base.html具有默认值的{% block content %}模板，并且该模板正在扩展base.html. 所以我试过这个：
{% extends "base.html" %}
{% if condition == True %}
{% block content %}
<div>blah blah blah blah</div>
{% endblock content %}
{% endif %}
and I was expecting to see blah blah blah blahif condition was true and see the default block if it wasn't true.
我期待查看blah blah blah blah条件是否为真，如果不为真，则查看默认块。
But both times I got blah blah blah blah.
但两次我都得到了blah blah blah blah。
Then I tried this one:
然后我尝试了这个：
{% extends "base.html" %}
{% if condition == True %}
{% block content %}
<div>blah blah blah blah</div>
{% endblock content %}
{% else %}
{% block content %}
<div>The Default Thing</div>
{% endblock content %}
{% endif %}
and I got this error:
我收到了这个错误：
TemplateAssertionError: block 'content' defined twice
How can I put a block inside an ifstatement?
如何在if语句中放置一个块？
采纳答案by Martijn Pieters
You cannot make a {% block %}conditional; once you use the tag, the block is always going to be filled in.
你不能{% block %}有条件；一旦你使用了这个标签，这个块总是会被填满。
Put your conditional insidethe block instead, and use super()to instruct Jinja to use the original contents of the block as defined in the template:
将您的条件放在块中，并用于super()指示 Jinja 使用模板中定义的块的原始内容：
{% extends "base.html" %}
{% block content %}
{% if condition %}
<div>blah blah blah blah</div>
{% else %}
{{ super() }}
{% endif %}
{% endblock content %}
