Check to See if Field Exists

Question

When looping through a matrix, is there aquick way to check whether or not the block has a particular field (not if the field is empty, but if the field exists at all).

I have a matrix with ~20 block types, 12 or so have a field called blockTitle. For in-page nav, I'd like to loop through all the blocks and just output blockTitle for those that do have it. I could do this with a conditional for block.type, but am wondering if there's a simpler check (in case we add more block types in the future, don't want to have to update the conditional every time).

Using {% if block.blockTitle %} will kick back "Craft\MatrixBlockModel and its behaviors do not have a method or closure named "blockTitle"." for block types without that field, so that's a no go.

Tks.

Answer 1

This should work:

{% if block['blockTitle'] is defined %}
    // Do your thing
{% endif %}

Answer 2

It is possible to set custom field parameters on Matrix block queries (→ Craft 2.3 release notes). And looking for non empty fields is possible with :nonempty: (also not documented but mentioned in the 2.0 release notes).

{% set blocksWithTitle = entry.myMatrixField.myTitleField(':notempty:') %}

{% for block in blocksWithTitle %}
    {{ block.myTitleField }}
{% endfor %}

Answer 3

The most reliable method i've found to test if a matrix field is defined is using the length twig filter:

{% if entry.myMatrixField | length %}
  {% for block in entry.myMatrixField %}
    <p>Matrix blocks here.</p>
  {% endfor %}
{% else %}
  <p>Matrix not defined.</p>
{% endif %}

More on this in the Craft CMS docs here.