Custom PHP Functions: String functions
It's now time for some PHP that isn't Cake related. This is the first part in a series of "Basic/Common PHP functions that all programmers should know". This series has to deal with manipulating strings. I try to make my functions short, sweet and powerful, and I hope you learn something from them.
Truncate
This function takes a long string and shortens it to a defined length and adds appends an ellipsis (or custom string) to the end. Instead of chopping a word in half (if the limit finished within it), it moves the pointer up to the previous space.
/**
* Truncates a string to a certain length.
*
* @param string $text
* @param int $limit
* @param string $ending
* @return string
*/
public function truncate($text, $limit = 25, $ending = '...') {
if (strlen($text) > $limit) {
$text = strip_tags($text);
$text = substr($text, 0, $limit);
$text = substr($text, 0, -(strlen(strrchr($text, ' '))));
$text = $text . $ending;
}
return $text;
}Shorten
This function works similarly to truncate(), but instead of chopping off the end of the string, it chops out the middle. This is useful for shortening users long names or websites.
/**
* If a string is too long, shorten it in the middle.
*
* @param string $text
* @param int $limit
* @return string
*/
public function shorten($text, $limit = 25) {
if (strlen($text) > $limit) {
$pre = substr($text, 0, ($limit / 2));
$suf = substr($text, -($limit / 2));
$text = $pre .' ... '. $suf;
}
return $text;
}Obfuscate
Now this function doesn't directly scramble the text and confuse the user, instead it scrambles the source code. This is useful for displaying emails or other strings that you don't want to show up directly in your source code.
/**
* Scrambles the source of a string.
*
* @param string $text
* @return string
*/
public function obfuscate($text) {
$length = strlen($text);
$scrambled = '';
for ($i = 0; $i < $length; ++$i) {
$scrambled .= '&#' . ord(substr($text, $i, 1)) . ';';
}
return $scrambled;
}Slugify
This function takes a string and makes it SEO and URL friendly (for example in the address bar for my blog posts). It lowercase's all words, replaces spaces with a dash, removes foreign/illegal characters and follows the guidelines for the best possible SEO. For example "Hello, my name is Miles Johnson!" would convert to "hello-my-name-is-miles-johnson".
/**
* Rewrite strings to be URL/SEO friendly.
*
* @param string $text
* @return string
*/
public function slugify($text) {
$text = trim(strtolower($text));
$text = str_replace(array('-', ' ', '&'), array('_', '-', 'and'), $text);
$text = preg_replace('/[^a-zA-Z0-9\-_]/is', '', $text);
$text = urlencode($text);
return $text;
}Listing
This final function takes an array of items and turns them into an ordered list with the last item having the word "and" in front of it instead of a comma. Very good for making lists.
/**
* Creates a comma separated list with the last item having an "and".
*
* @param array $items
* @param string $and
* @return string
*/
public function listing($items, $and = 'and') {
if (is_array($items)) {
$lastItem = array_pop($items);
$items = implode(', ', $items);
$items = $items .' '. $and .' '. $lastItem;
}
return $items;
}Now that's all I have for now, and I know you will use this in your code constantly just like I do! Be patient for my next series which will be dealing with basic date/time functions.