Saving multiple categories id in string.

[Xymor]

Hi. 

My module renders category tree using helper form ​'type' => 'categories'.

How can i save selected ID in string separated by comma?

 

[shacker]

$skipman2[] = Tools::getValue('skipman');

 

foreach($skipman2[0] as $key => $value)

$skipman .= $value.',';

$skipman = trim($skipman, ",");

 

 

 

Tools::getValue('skipman'); is the name of the element that have the categories