wordpress has thumbnail code example
Example 1: wordpress if thumbnail show else
<?php if ( has_post_thumbnail() ) {
the_post_thumbnail();
} else { ?>
<img src="<?php bloginfo('template_directory'); ?>/images/default-image.jpg" alt="<?php the_title(); ?>" />
<?php } ?>
Example 2: show featured image in post wordpress
<?php if(has_post_thumbnail()){
the_post_thumnbail('cstm_name', array( 'class' => 'class1 class2' ))
} else { ?>
<img class="card-img-top" src="http://placehold.it/750x300" alt="Card image cap" class="img-responsive">
<?php } ?>