Common filter hooks in Wordpress - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a filter hook in WordPress?

A filter hook lets you change or modify data before it is used or displayed. It acts like a checkpoint where you can adjust content or values.

beginner

Name a common filter hook used to modify the content of a post before it displays.

The the_content filter hook lets you change the post content before it shows on the site.

beginner

How do you add a function to a filter hook in WordPress?

Use add_filter('hook_name', 'your_function'). This tells WordPress to run your function when the filter runs.

intermediate

What does the excerpt_length filter hook do?

It lets you change how many words show in the post excerpt summary.

beginner

Why use filter hooks instead of changing core WordPress files?

Filter hooks keep your changes safe during updates and let you customize behavior without touching core code.

Which function is used to attach your function to a WordPress filter hook?

A add_filter()

B add_action()

C apply_filters()

D do_action()

add_filter() attaches your function to a filter hook so it can modify data.

What does the the_title filter hook allow you to do?

A Change the post author

B Change the post content

C Change the excerpt length

D Change the post title before display

the_title filter lets you modify the post title before it shows on the site.

Which filter hook would you use to change the number of words in a post excerpt?

A the_excerpt

B post_excerpt

C excerpt_length

D excerpt_more

excerpt_length controls how many words appear in the excerpt.

What is the purpose of the apply_filters() function?

A To run all functions attached to a filter hook and return modified data

B To add a new filter hook

C To remove a filter hook

D To execute an action hook

apply_filters() runs all functions attached to a filter and returns the final data.

Why should you avoid editing WordPress core files directly?

A Because core files are read-only

B Because updates will overwrite your changes

C Because it slows down the site

D Because it disables plugins

Editing core files risks losing changes when WordPress updates. Filters let you customize safely.

Explain what a WordPress filter hook is and how it works.

Think about how you can change text or values before they show on your site.

List three common WordPress filter hooks and what they modify.

Focus on content, title, and excerpt filters.