There are two ways I got this done (any of these will work):
1.
content.php is the file that controls this aspect, you should look to that file to change the_content to the_excerpt (for the right conditional tags).
PS: If this affect the main post/page display, then you need a condition to be added, such as:
if ( is_singular() ) {
the_content();
} else { the_excerpt(); }As you’ll have to change the theme’s code, make sure you’re working in a child theme.
2.
You can edit the theme OR the child theme functions.php file:
/* Replace the content with excerpts on home page */
add_filter( 'the_content', 'replace_content_with_excerpt', 100 );
//http://wordpress.stackexchange.com/a/77947/25187
/**
* Return excerpt if we are not on a singular post view.
*
* @param string $content
* @return string
*/
function replace_content_with_excerpt( $content ) {
if ( is_singular() ) {
return $content;
}
// remove our filter temporarily.
// Otherwise we run into a infinite loop in wp_trim_excerpt().
remove_filter( 'the_content', __FUNCTION__, 100 );
$excerpt = apply_filters( 'the_excerpt', get_the_excerpt() );
add_filter( 'the_content', __FUNCTION__, 100 );
return $excerpt;
}