How to limit wordpress the_excerpt() dynamically

Question

I'm trying to limit WordPress post excerpt and I've tried some ways to do it but all of them was not the stuff that I need, to say concisely I want to limit post excerpt with a number that I use everywhere with differences.

For example, I need to make something I use it like this: <?php the_excerpt('30') ?> with this part of the code, I wanna limit my excerpt to 30 chars and in another place, I wanna use a different value like: <?php the_excerpt('150') ?> Is it in WordPress?

Answer 1

You can shorten the excerpt with something like this:

function shorten( $s, $num, $dots ) {
        if ( $num < mb_strlen( $s ) ) {
            $fs = mb_substr( $s, 0, $num );

            for ( $i = mb_strlen( $fs ); $i >= 0; $i -- ) {
                if ( mb_substr( $fs, $i, 1 ) == ' ' ) {
                    return mb_substr( $fs, 0, $i + 1 ) . $dots;
                }
            }

            return $fs . $dots;

        } else {
            return $s;
        }
    }

You can then call it like that: shorten(get_the_excerpt(), 40, '...') (replacing the dots with something else or nothing, if you like).

(Source)