Smarty: replace middle part of string - smarty

Question

Hello I have a smarty variable which has values like (Number, Number, Number) and I would like to replace the middle part:
2, 3, 4, 5, 6 -> 2-6
1, 2, 3, 4 -> 1-4
7, 8, 9, 10, 11 -> 7-11
So basicaly I want to first and the last number to be combined by a "-" the rest should be removed. How can I achieve this in smarty?
Thanks in advance!

Answer 1

Smarty is a templating system. It's main purpose is to represent the data it receives from the PHP code (in variables) as HTML or any other text format.
The easiest way to do transformations like the one you need is to prepare them in the PHP code and assign them to variables.
On the other hand, such a transformation is not a business rule but a presentation detail; accordingly, it must be implemented in the view (Smarty) and not in the model (the PHP code).
The best solution for Smarty is to write a Smarty plugin (a modifier) that implements this transformation.
This is a simple example of how such a modifier could look like:
/**
* Smarty modifier plugin
*
* #param string|array $range input string or array
* #param string $separator the value to use as separator (e.g. '...')
* #return string
*/
function smarty_modifier_range($range, $separator = '-')
{
// If the input is a string (like "1,2,3,4"), convert it to an array
if (is_string($range)) {
$range = explode(',', $range);
} elseif (! is_array($range)) {
// If it's neither string, nor array then
// this modifier has no effect on it
return $range;
}
// A range must have at least two components
if (count($range) < 2) {
// It's not a range
return implode(',', $range);
}
// Use only the first and the last item
return reset($range).$separator.end($range);
}
In order to use it you have to tell Smarty where to find it. Create a directory for this plugin (maybe you will write more Smarty plugins) and put the function in a file named modifier.range.php in this directory.
Use the Smarty function addPluginsDir() during the initialization of your Smarty object to add this directory to the list of directories where it looks for plugins.
$smarty = new Smarty();
$smarty->addPluginsDir(array('... the path of the new director here'));
The modifier accepts arrays and strings that contain values separated by comma. It extracts from them the first and the last component (if there are at least two components) and return them joined by a configurable separator (default: -):
$smarty->assign('var1', range(12, 16));
$smarty->assign('var2', array(7, 8, 9, 10, 11));
$smarty->assign('var3', '2,3,4,5,6');
$smarty->assign('var4', '4');
$smarty->assign('var5', array(5, 10, 15));
$smarty->assign('var6', array(3, 5, 6, 4));
In templates:
{$var1|range} // 12-16 (modify array)
{$var2|range:".."} // 7..11 (use custom separator)
{$var3|range} // 2..5 (modify string)
{$var4|range} // 4 (there is no range here)
{$var5|range} // 5-15 (doesn't verify for gaps)
{$var6|range} // 3-4 (doesn't verify the order)
The last example shows a drawback of the plugin as it is exposed above. It doesn't verify if the values in the input array or string are sorted in the ascending order. Therefore, if they are not already sorted, its output is not quite correct.
However, this is a minor issue that can be easily solved using the sort PHP function.
Update: a more elaborate version of the plugin can be found on Github.

Answer 2

Are you sure that your variable is a string and not an array?
For an array: You could use foreach loop to process all array elements, but display only first and the last items.
Here is exactly what you need:
http://www.smarty.net/forums/viewtopic.php?p=3219
But for a string you could explode it on "," to get an array or regex_replace modifier:
http://www.smarty.net/docsv2/en/language.modifier.regex.replace.tpl

Answer 3

in java you can do this:
List<String> splitedList = Arrays.asList(variable.split(","));
String finalString=splitedList.get(0)+"-"+splitedList.get(splitedList.size()-1);