Get terms parent ID for conditional IF statement

Question

I have the following working code to echo the name of the term (taxonomy called prodcats) that a series of posts are in. This is in the taxonomy archive template taxonomy-prodcats.php

$terms = get_the_terms( $post->ID , 'prodcats' );
foreach( $terms as $term ) {
    echo '<div class="categoryblock">';
    echo '<h3>' . $term->name . '</h3>';
    echo '</div>';
    unset($term);
}

What I need to do is have the "categoryblock" div a different background color depending on what parent term is being used. There are 5 parent terms in total with IDs 3,4,5,6 and 7.

So, how do I adapt the above to say if this terms parent is 3, then echo x else if terms parent is 4, echo y else if terms parent is 5, echo z etc.. (you get the picture).

I tried several things including $parent = $term->parent; echo $parent->id; but this didn't output anything.

Answer 1

While this is not specifically WordPress but some general PHP, here's a solution which you could use:

$terms = get_the_terms( $post->ID , 'prodcats' );
foreach( $terms as $term ) {
    $classes = 'categoryblock';

    switch( $term->parent ) {
        case 3:
            $classes .= ' blue'  // Notice the space between the opening string - important for CSS
          break;
    }

    echo '<div class="' . $classes . '">';
    echo '<h3>' . $term->name . '</h3>';
    echo '</div>';
    // unset( $term ); // I'm not sure this works and it would be unnecessary
}

So, we are using a PHP Switch at the top to append our class name to a string. Whenever a $term->parent == 3 PHP will append blue to the string $classes so it will look like this: categoryblock blue which then will get added to the <div/> class attribute. This is assuming you have a .blue{color:blue} class in your CSS stylesheet.

On another note, there's no need to unset anything from your terms array unless you're going to be doing addition operations with that array later. PHP Foreach will iterate through the array once from top to bottom.