The post_class() WordPress PHP function displays the classes for the post container element.
Usage
post_class( $css_class, $post )
Example:
<div id="post-<?php the_ID(); ?>" <?php post_class( 'custom-class' ); ?>>
Parameters
$css_class(string|string[]) Optional. One or more classes to add to the class list. Default:''$post(int|WP_Post) Optional. Post ID or post object. Defaults to the global$post. Default:null
More information
See WordPress Developer Resources: post_class()
Examples
Add a single class
Add a single class to the post_class defaults:
<div id="post-<?php the_ID(); ?>" <?php post_class( 'class-name' ); ?>>
Add multiple classes
Use an array to add multiple classes:
$classes = array( 'class1', 'class2', 'class3' ); ?> <div id="post-<?php the_ID(); ?>" <?php post_class( $classes ); ?>>
Specify a different post ID
To print post_class CSS classes for a post other than the current one, specify its ID (integer):
post_class( '', 22 );
Default usage in a theme file
This example shows the post_class template tag as commonly used in a theme file (such as single.php):
<div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
Add multiple classes as a string argument
A simple way to add multiple classes to the post_class defaults, is to just write them as a string argument:
<div <?php post_class( 'class1 class2 class3' ); ?>>