If Meta Checkbox is checked, do something?

You’re setting a value whether it’s checked or not with this line:

$chk = ( isset( $_POST['special_box_check'] ) && $_POST['special_box_check'] ) ? 'on' : 'off';

The value is going to be either on or off, so your if condition is always true, since it always has a value.

You could change it to save only if it’s checked, or delete it if it’s not. That way your condition will work, and you won’t have extra meta entries just to save the off state.

if ( isset( $_POST['special_box_check'] ) && $_POST['special_box_check'] ) {
    add_post_meta( $post_id, 'special_box_check', 'on', true );
} else {
    delete_post_meta( $post_id, 'special_box_check' );
}

Related Posts:

  1. How to update custom fields using the wp_insert_post() function?
  2. Most efficient way to add javascript file to specific post and/or pages?
  3. Display all values of custom a field created with ACF on a page
  4. Adding custom input for data attribute in insert media modal
  5. How to automatically apply woocommerce product title to all product images alt tags?
  6. How to handle a custom form in wordpress to submit to another page?
  7. If Custom Field is empty don’t display div
  8. How to display multiple Post meta_key/meta_values by SQL query
  9. Custom Meta Field – Youtube embed
  10. WooCommerce: How to display item meta data in email confirmation using woocommerce_order_item_meta_end
  11. How to make an meta_query optional?
  12. How to use multiple query with same meta key
  13. How can i create a function to get youtube video time
  14. Getting movie and serial on actor page
  15. How to loop over custom fields in a page template?
  16. Add custom field to attachments in a specific category
  17. Match checkbox data with page title to show certain items
  18. Print html when custom field has value inside while loop
  19. Update WordPress Custom Field with AJAX on cached page
  20. Geocoding an Exploded Custom Field Array
  21. How can update custom meta for all posts
  22. Unique key for each row in a repeater field
  23. Trying to retrieve meta values from three different meta keys and display in rows
  24. WP post meta – for loop inside for loop
  25. custom fields anchor points php
  26. Store custom field’s multiple values in one user meta key
  27. Get field in readable word
  28. WooCommerce multiple custom fields code
  29. When working with a post, almost all wp_postmeta are deleted
  30. What syntax is this? “{{post.price}}”
  31. Updating Lat and Lng of posts automatically gives sporadic results
  32. How to display custom field from a gallery thumbnail?
  33. WP_query meta_query slow with OR and DATES
  34. Get meta_query value by user meta array
  35. How to use something like meta_query but for fields?
  36. Getting a value from a custom field from a page that shares a parent with the current page
  37. meta field for numerous links
  38. Custom fields changes the formatting of metabox input
  39. Include a custom field in mysql query
  40. Display Content Based on Custom Field Value
  41. php if, else & custom fields – syntax error
  42. How to get the first letter from custom field?
  43. Meta box not saving spaces
  44. divide custom field values in div every two values
  45. custom field meta-box with dropdown/autocomplete
  46. Showing custom field contents without listing description
  47. How to exclude post from being queried based on custom meta value
  48. If custom field doesn’t exist, or exists and it’s true show title?
  49. How to link a word comprised of a custom field with another?
  50. Custom field in title
  51. If Elseif Query
  52. How can I put a custom field as the link of a button shortcode?
  53. Outputting a custom field in PHP
  54. Sorting Meta Fields?
  55. Custom fields randomly stop working
  56. Display selected parts from selected pages on the frontpage?
  57. Where can I find the code for the menu page meta boxes?
  58. How to echo a different field if another field is empty?
  59. How to use custom fields to replace top-level parent title with an image using wp_list_pages?
  60. PHP Puzzle: Unique Styles with PHP loop
  61. I want Page titles and excerpts to show up on home.php in certain order
  62. Posts sortable column not sorting properly for custom field numbers
  63. Search result page – display values from the result’s metaboxes
  64. Display custom meta box in my template file
  65. Query posts by custom fields (object post)
  66. ACF Date fileds to Age Convert [closed]
  67. Save custom field value to variable for conditional – why is this not working? [closed]
  68. Metadata on the WP_Post object
  69. Appending an ACF custom field to the page title
  70. Too many if’s and else if’s ?? – Must be better way [closed]
  71. Advanced Custom Fields Show PHP in Text Areas
  72. WP query with variables gives no result for specific user
  73. Grabbing value of input field inside of array
  74. Displaying custom meta box value in a custom post page
  75. How to initialise WP_Query on the basis of a specific meta_value and continue iterating rest?
  76. Convert custom field date format to “WordPress default”
  77. I want to show image from custom field image on my custom page template
  78. How can I change the location where the custom field is displayed in the Quick Edit tab in WordPress
  79. How do I organize posts based on their taxonomy?
  80. How do you create a front end form that enables the editing of member-specific custom fields in WordPress?
  81. Search custom post type posts only by meta fields?
  82. How to pass value to add_filter wpcf7_form_tag from another function?
  83. Custom Admin Menu Report for Specific User ID
  84. Shortcode Displays 2 times
  85. How to execute a shortcode within a custom field?
  86. ACF number less than comparison not working
  87. fetch from an external api call and display results in page
  88. Problem with custom user fields default value and retrieval
  89. Cannot Access ACF Field Values via my Plugin
  90. wordpress-plugin (widget) that performs a Neaby-search on the openstreetmap-endpoint: around x find y
  91. How to create advanced custom fields for backend content
  92. ACF block gutenberg aligncenter don’t work
  93. How to pull through page title depending on which radio button is selected on the specific page?
  94. Display WooCommerce Order Custom Field In Template (HPOS)
  95. How can I display a layout differently depending on whether the user is on Mobile or PC?
  96. hide “Open in New Tab” checkbox in link field
  97. Want to add custom post type for facebook feed
  98. Exclude function for custom pages, exclude custom ACF fields
  99. Custom rest fields not loaded in rest api cpt response
  100. Display posts in correct month order using single date custom field
Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)