Does hooking into a plugin action / filter override the plugin’s function for that hook?

It depends entirely on the specific plugin and the specific hook. It’s completely up to plugin developers what they want to allow other developers to do. They could allow developers to replace entire functions; to perform a custom action at the beginning, middle, or end of a function; to modify the result of a function; or none of the above. It’s impossible to give a generic answer.

The only way to know what you can do is to consult the developer documentation for the plugin, which will tell you what you can do. If that doesn’t exist, reading the actual code of the plugin and looking for hooks is all you can do.

Related Posts:

  1. Using filters and actions for plugin API?
  2. When is it appropriate to put functions on page template vs. functions.php?
  3. When to check if a function exists
  4. Dynamically Override Fancy Title
  5. What function to hook for changes made in status and visibility of a post
  6. Can I differentiate between “Delete Post Permanently” and “Empty Trash” and do something for each accordingly?
  7. WordPress after content Hook & external template part
  8. get_current_screen() return null
  9. Maximum lifetime for nonce
  10. How to use a hook to override an update_post_meta call in a plugin?
  11. Adding option to Gallery shortcode
  12. correct way to call javascript into hook function
  13. How to modify files inside wp-includes directory in wordpress
  14. Call to undefined function is_home() or any conditional tags
  15. How to replace settings in WordPress plugin from a theme
  16. Customise Grouped Product display in Woocommerce with custom column
  17. Add function to Dokan ajax class
  18. Function not working on any file other than the main plugin file
  19. Template file structure , wordpress hook for altering the template
  20. Dynamic banner for use on external sites
  21. get_term_by() returning null on plugin
  22. Custom fields in the billing address section woocommerce
  23. In Which Contexts are Plugins Responsible for Data Validation/Sanitization?
  24. Plugin Form Submission Best Practice
  25. Best way to abort plugin in case of insufficient PHP version?
  26. Where to put third party PHP library?
  27. Add a new tab to WordPress Plugin install Listing
  28. Optimize shortcode callbacks
  29. Changing Plugin Load Order
  30. How to integrate a PHP webmail script into the backend of WordPress?
  31. How should you hook a session_start() when authoring a plugin?
  32. Init action hook running late after PayPal’s return url?
  33. How to log plugin errors to plugin error_log file
  34. How Do I Load My Action Earlier Enough?
  35. Which to use to execute code during the saving of a plugin settings page?
  36. I can’t find where a hook is being defined in a plugin – Easy Digital Downloads
  37. Custom theme sufficient or custom plugin neccessary for this feature set?
  38. How do I handle multiple Submit buttons in plugin’s option page?
  39. How to create custom home page via plugin?
  40. Set default options for inserting media
  41. Adding callback function for wp_ajax_ has no effect
  42. Hook for post permalink update
  43. Featured Image not showing in admin
  44. How to change post status from publish to draft using hook in wordpress?
  45. Plugin development: is adding empty index.php files necessary?
  46. Create a plugin to change the action to which a function is hooked
  47. comment_email hook doesn’t seem to work for comment editor field
  48. Post thumbnail relative link and HTML modify
  49. How do I change the initial quantity of a product in woocommerce?
  50. Where and how does WordPress store and use its plugin and hook information?
  51. Widget update function not saving values
  52. Which are the hooks run before/after when a category’s deletion?
  53. edit_{$taxonomy} | Hook
  54. override pluggable.php functions
  55. Disable The Events Calendar plugin from loading its scripts
  56. creating custom function to log actions in plugin
  57. Where to add hooks in a class
  58. How to customize a permalink (URL) structure?
  59. Custom Taxonomy to dropdown box on adminside wordpress
  60. How to use output buffering in WordPress hooked functions?
  61. do_action and add_action on two different installed plugins won’t work
  62. Incorporate small angular feature in my wordpress site
  63. Modify custom field input data before creating a new post
  64. I have 2 plugins using the same wp_login action hook and one is not working
  65. Add a new confirmation page before saving
  66. WordPress class, using add_action to call member function does not work
  67. How dynamic action login_form_{action} is working
  68. How should I go about registering JavaScript that isn’t a file? [duplicate]
  69. What happens when two or more plugins use the same hook?
  70. Add child pages to submenu automatically
  71. Why in this archive page that call query_posts() function show only the last 10 posts?
  72. Add an Outside Wrapper to my Header and Make it Full Width
  73. Converting core modification to a plugin
  74. Ajax +wordpress onClick link redirect to new page and create html content
  75. Remove Permalink Meta Box not working?
  76. Setting post_id for single.php based on URL without a redirect
  77. Serial Number from custom table not appear in woocommerce_email_before_order_table action
  78. Creating posts with links from a txt file
  79. Change the behaviour of a button
  80. Action / Hook when a new plugin is added
  81. apply_filters() and call_user_func() to define and call a function outside a class
  82. How to create a custom post-new.php page for plugin , no wp menu
  83. Want to know how to reveal a WordPress theme, considering the theme name is hidden?
  84. The function called on the wp head hook becomes null
  85. Redirection from a specific page for users logged in but not with membership
  86. Save meta box data from selected dropdown list in bbpress reply form
  87. working code, not working – Plugin Dev
  88. Is there any way to get post meta from publish_post hook?
  89. Prevent plugin activation and add admin notice
  90. foreach argument to get specific file types getting too many returns
  91. Does WordPress have something like timer hook?
  92. Change the search results header from plugin
  93. Custom options page for themes
  94. Call do_action() within WordPress cronjob
  95. How can I get a plugin to hook ‘dbdelta_queries’ — a filter used during version update?
  96. Send retrieve password notification email with custom HTML email template
  97. Extend WP_List_Table class – Edit wp_usermeta – WPPB.me Boilerplate – Action error
  98. wp_head is not fired from the hook I have used in my plugin
  99. How to Add Extra Text In WordPress Title Before Post Publish
  100. Developing an IP lookup function using an API