Block Logic – Full Gutenberg Block Display Control

September 24, 2023

Block Logic – Full Gutenberg Block Display Control Plugin

Block Logic adds a "Block Logic" field to the block editor, that lets you show or hide any block based on conditions.

Block Logic adds a “Block Logic” field to the “Advanced” section of the block editor (i.e Gutenberg), that lets you show or hide any block based on conditions. You can use WordPress’ Conditional Tags or any general PHP code.

Show or hide blocks based on

User role
User login status
Post status
Date and time
The result of a custom PHP function

Features

Show or hide any block using conditions
Combine conditions with “and” or “or” operators. See FAQ Writing Logic Code
Full flexibility: use any condition you want

Limitations

Does not work with the Classic Block, Widget Block or Widget Area Block [‘core/freeform’, ‘core/legacy-widget’, ‘core/widget-area’], as the those blocks do not support block attributes. Does also not work with the HTML Block [‘core/html’] inside the Widget Screen, as this one also does not support block attributes there.

Configuration

Just activate the plugin. The “Block Logic” textbox will then appear in the “Advanced” section of the Gutenberg editor.

Screenshots

The 'Block logic' field at work in the block editor.

FAQ

Writing Logic Code

Make good use of WP’s own conditional tags. You can vary and combine code using:

! (not) to reverse the logic, eg !is_home() is TRUE when this is NOT the home page.
|| (or) to combine conditions. X OR Y is TRUE when either X is true or Y is true.
&& (and) to make conditions more specific. X AND Y is TRUE when both X is true and Y is true.
is_home() — just the main blog page
!is_page('about') — everywhere EXCEPT this specific WP ‘page’
is_user_logged_in() — shown when a user is logged in
is_category(array(5,9,10,11)) — category page of one of the given category IDs
is_single() && in_category('baked-goods') — single post that’s in the category with this slug
current_user_can('level_10') — admin only blocks
strpos($_SERVER['HTTP_REFERER'], "google.com")!=false — blocks to show when clicked through from a google search
is_category() && in_array($cat, get_term_children( 5, 'category')) — category page that’s a descendent of category 5
global $post; return (in_array(77,get_post_ancestors($post))); — WP page that is a child of page 77
global $post; return (is_page('home') || ($post->post_parent=="13")); — home page OR the page that’s a child of page 13

Note the extra ‘;’ on the end where there is an explicit ‘return’.

The ‘block_logic_eval_override’ filter

Before the Block Logic code is evaluated for each block, the text of the Block Logic code is passed through this filter. If the filter returns a BOOLEAN result, this is used instead to determine if the block is visible. Return TRUE for visible.

With great power comes great responsibility

The block logic you introduce is EVAL’d directly. Anyone who has access to use the Gutenberg Editor will have the right to add any code, including malicious and possibly destructive functions. There is an optional filter ‘block_logic_eval_override’ which you can use to bypass the EVAL with your own code if needed.

I’m getting “PHP Parse error… … eval()’d code on line 1”

You have a PHP syntax error in one of your block’s “Block Logic” fields. Review them for errors.

Changelog

1.0.8

recompiled assets to remove console.log

1.0.7

added logic indicator to mark blocks that have logic applied

1.0.6

added check for Classic Block, Widget Block or Widget Area Block [‘core/freeform’, ‘core/legacy-widget’, ‘core/widget-area’], as those do not support block attributes
added limitations to plugin description
updated dev dependencies

1.0.5

added check for Classic Block and disabled display of settings there

1.0.0

Initial Release of the plugin