This function is similar to two native functions from CI (ellipsize and character_limiter) but more ruthless (non-preserves words), flexible (dont alters or strip anything in your string, because you can do it easily if necessary) and accurate (passed in

text_helper.php

<?php defined('BASEPATH') OR exit('No direct script access allowed.');

/**
 * Character Limiter Mid
 *
 * Limits the string representing the characters removed from somewhere from
 * their mid. This limiter considers the output string as two parts (start and
 * end) and not preserves complete words, so you also can chose exactly how many
 * characters at start and end you need have.
 *
 * @access	public
 * @param	string  The input string
 * @param	mixed   Limit count (eg. 20) or an array assigning lengths of start and end (eg.: array(15, 5)) to your output
 * @param	string	The mid character. Usually an ellipsis
 * @return	string
 */
function character_limiter_mid($str, $n = 20, $mid_char = '&#8230;')
{
	// Getting params
	// @param int $n Number of max lenght
	// @param int $a Length of start part
	// @param int $b Length of end part
	if (is_array($n) && sizeof($n = array_filter($n, 'is_numeric')) === 2)
	{
		list($a, $b) = $n;
		$n = array_sum($n);
	}
	elseif (is_numeric($n))
	{
		$a = ceil($n/2);
		$b = $n-$a;
	}

	// Are anything to do?
	if (isset($a, $b) && $n > 0)
	{	
		// Is the string long enough to be limited?
		if (strlen($str) > (strlen($mid_char)+$n))
		{
			// No has end part?
			if ($b <= 0)
			{
				$str = substr($str, 0, $a) . rtrim($mid_char);
			}
			// No has first part?
			elseif ($a <= 0)
			{
				$str = ltrim($mid_char) . substr($str, -$b);
			}
			// Has both parts!
			else {
				$str = substr_replace($str, $mid_char, $a, -$b);
			}
		}

		// Work completes!
		return $str;
	}
}

/* End of file text_helper.php */