Add a custom class to the body tag using custom fields

You want to use body_class filter.

function prefix_add_body_class( $classes ) {
    global $post;

    // good to check
    if( ! is_single() || 'post' !== get_post_type() ) {
        return $classes;
    }

    $btag = get_post_meta( $post->ID, 'tagbody', true );

    if ( empty( $btag ) ) {
        return $classes;
    }

    $classes[] = $btag;

    return $classes;
}
add_filter( 'body_class', 'prefix_add_body_class' )

EDIT:

You wrote me in the comments that the theme is your own theme. So you don’t need to do it via a filter. Just do it right in your theme.

Edit the header.php file like this.

// some code above
$classes = array();

if( is_single() && 'post' === get_post_type() ) {
    $btag = get_post_meta( $post->ID, 'tagbody', true );

    if( ! empty( $btag ) ) {
        $classes[] = $btag;
    }
}
?>
<body <?php body_class( $classes ); ?>>
<?php
// some code below

Related Posts:

  1. How to update custom fields using the wp_insert_post() function?
  2. How to display multiple Post meta_key/meta_values by SQL query
  3. WooCommerce: How to display item meta data in email confirmation using woocommerce_order_item_meta_end
  4. How to use multiple query with same meta key
  5. How can update custom meta for all posts
  6. Use ajax to update_post_meta
  7. how to increase custom post value by one most efficiently?
  8. How can I create a list of page titles from custom meta values?
  9. Store multiple custom field as post meta per post(css, js, html, 2 link) [closed]
  10. How to VAR_DUMP a $variable during checkout process (Is my product meta callable?)
  11. Is it possible to retrieve all posts with a certain value for metadata?
  12. Non-Closing PHP Query in WordPress Loop
  13. how to get serialized post meta
  14. WordPress loop by meta key that is an array? and how loop multiple arrays
  15. How to store multiple custom meta box
  16. Order a WP_Query by meta value where the value is an array
  17. Define category ID using get_post_meta
  18. Hide a div when a custom field is empty
  19. WordPress stripping out custom field tags
  20. Order category posts by last word of custom field
  21. Add a “custom field” to a category that can be retrieved when viewing the category page with get_post_meta
  22. Display custom field value in woocommerce variable product via jQurey
  23. How to update custom fields when post is published?
  24. How do I get the value of a current user’s custom field?
  25. WP post meta – for loop inside for loop
  26. When working with a post, almost all wp_postmeta are deleted
  27. Updating Lat and Lng of posts automatically gives sporadic results
  28. If custom field doesn’t exist, or exists and it’s true show title?
  29. Metadata on the WP_Post object
  30. Using register_activation_hook in classes
  31. Get meta_id along with meta_key and meta_value
  32. How can merge two arrays values in one array and save in database
  33. How to handle a custom form in wordpress to submit to another page?
  34. post meta data clearing on autosave
  35. How to Remove a Filter from the Admin List Table?
  36. Compare two meta key values against each other inside the get_posts array?
  37. Woocommerce, recognize the loop of related products
  38. Removing WordPress profile fields from non-admins
  39. Show custom field if it exists, and show different elements if it doesn’t
  40. Change description on specific WooCommerce product status change
  41. Custom field value not saving when it contains a URL?
  42. How to add a second ‘place order’ button in WooCommerce [closed]
  43. How to do multiple searches (with logical OR) in WP_Query in hook pre_get_posts?
  44. tracking number field in Woocommerce order [closed]
  45. Sort posts by custom fields value using dropdown menu
  46. Creating user status mode in WordPress
  47. Need Help Fixing My Iframes [closed]
  48. Add a product to checkout via form
  49. Why ajax doesn’t work on certain wordpress hooks and reload the page instead?
  50. Return a numerical function value in Customizer controls
  51. Trouble checking if custom woocommerce checkout field is empty or not
  52. edit_comment_link is not showing for comment author
  53. Adding function to Genesis genesis_header [closed]
  54. Add / Update Custom Fields After Select Pictures in Media Window
  55. Remove the last X characters of a custom field value
  56. Password minimum length in personal subscription [closed]
  57. Why are the details of my todo not saving?
  58. Theme activation hook in php class
  59. Can’t save php string to a custom field
  60. Remove empty terms from array, sort alphabetically, update back to repeating field
  61. WordPress yoast seo plugin – parse snippet var in meta description
  62. Changing the order of custom fields in the dashboard for Woocommerce variable products [closed]
  63. Handling repeater data
  64. How to add data to a custom field at the wp_users table?
  65. Using rules in Posts
  66. Save the value of a wp_dropdown_pages
  67. Add a counter for mouseovers (custom field)
  68. Show field if it has contents on Advanced Custom Fields
  69. the_meta – no get_the_meta query?
  70. Dynamically added custom fields not displayed on WooCommerce email notifications
  71. get value from get_post_meta then reuse it in another get_post_meta
  72. How can I add diffrent editable text fields?
  73. Include custom fields in search
  74. update_term_meta() only updating once on certain meta keys
  75. Loop for recently (updated_post_meta) posts?
  76. How to edit post meta data before publishing the post it self wordpress?
  77. Using zip code to display custom data in Admin Order Details
  78. Generating 3 random numbers and saving them in database
  79. ACF – Can’t get custom post type by taxonomy
  80. get Woocommerce product format json for WP_Query
  81. Is there an option to execute javascript file only on plugin activation
  82. update_post_meta Not Processing Array Data (Not Sure What I Am Missing)
  83. How do I remove an action hook inside a class that is called by another class?
  84. Hook into all password resets in WordPress and get password before hashing?
  85. What syntax is this? “{{post.price}}”
  86. Why transition_post_type hook is called twice for the same post?
  87. How to get the first letter from custom field?
  88. Meta box not saving spaces
  89. WordPress HTML Helper
  90. custom field meta-box with dropdown/autocomplete
  91. If Elseif Query
  92. get_post_meta is always empty when I use wp_mail
  93. Add custom fields after post/page title
  94. Display custom meta box in my template file
  95. How to display the date under the post title?
  96. Too many if’s and else if’s ?? – Must be better way [closed]
  97. Advanced Custom Fields Show PHP in Text Areas
  98. understanding wp_next_scheduled
  99. Convert custom field date format to “WordPress default”
  100. How to execute a shortcode within a custom field?
deneme bonusu veren sitelerbahis casinomakrobetceltabettipobet365pinbahispolobetgizabetaresbetlordbahisladesbetbetofbettrbettumbet