How to search for a string in a category name?

Question

I use the search result and I GET

$s = $_GET['s'];  

Which gives: "mario"

Now there is a category named Mario Bianchi under a main category called Persone

When I GET $s I need to get all posts within that category, I tried the following but I get nothing

$terms = get_terms( 'category', array(
    'name__like' => $s,
    'hide_empty' => true // Optional 
) );
if ( count($terms) > 0 ){
    echo '<ul>';
    foreach ( $terms as $term ) {
        echo '<li><a href="' . esc_url( get_term_link( $term ) ) . '" title="' . esc_attr( $term->name ) . '">' . esc_html( $term->name ) . '</a></li>';
    }
    echo '</ul>';
}

Yet I need the actual post attached, not the category itself

Answer 1

get_terms does just that, it get the terms for your query. What you'll want is WP_Query with a tax_query . You've already got the categories you want to return the posts for, so it shouldn't be too difficult

$terms = get_terms( array(
    'taxonomy'   => 'category',
    'name__like' => $s,
    'hide_empty' => true // Optional 
) );

$term_ids = array();

if ( ! empty( $terms ) ) {
    foreach( $terms as $term ) {
        $term_ids[] = $term->term_id;
    }

    $args = array(
        'post_type' => 'post',
        'tax_query' => array(
            array(
                'taxonomy' => 'category',
                'terms'    => $term_ids,
            ),
        ),
    );

    $query = new WP_Query( $args );

    if ( $query->have_posts() ) {
        echo '<ul>';
        while ( $query->have_posts() ) {
            $query->the_post();
            echo '<li><a href="' . esc_url( get_the_permalink() ) . '" title="' . get_the_title() . '">' . esc_html( get_the_title() ) . '</a></li>';
        }
        echo '</ul>';
    }
    wp_reset_postdata();

}