How to loop through Categories and then Posts within that category using Jekyll's liquid templates?

Question

I have the following layout:

---
layout: default
---
{% include header.html %}
<ul>
        {% for cat in site.categories %}
        <li>
                {% assign cat_name = cat[0] %}
                <div class="Projects">
                        <h1>{{ cat[0] }}</h1>
                        <h2>{{ cat_name }}</h2>
                        <ul>
                                {% for post in site.categories.cat_name %}
                                <li>
                                        <span class="date">{{ post.date | date: '%Y %b %d' }}</span> - <a href="{{ post.url }}">{{ post.title }}</a>
                                </li>
                                {% endfor %}
                        </ul>
                </div>
        </li>
        {% endfor %}
</ul>

This attempts to look through my site's categories and then for each one, assign the category name as "cat_name" and then for each of those, it uses {% for post in site.categories.cat_name %} to loop through the posts in that category.

This doesn't work. The line:

<h2>{{ cat_name }}</h2>

Does work. It shows "opinion" for instance which is one of the categories, so I know the assignment worked. And {% for post in site.categories.opinion %} works for instance. So its just something about passing that variable in there that's not working. How do I do this?

Answer 1

I should have done {% for post in site.categories[cat_name] %} instead of {% for post in site.categories.cat_name %}

That made it work for me.

Answer 2

我相信你想要的是使用capture构建一个使用类别名称的新变量，如Liquid文档中所述： https ： //shopify.github.io/liquid/tags/variable/

{% capture s_c_cat_name%}site.categories.{{cat[0]}}{% endcapture %} ... {% for post in {{s_c_cat_name}} %}