get random value from a PHP array, but make it unique

Question

I want to select a random value from a array, but keep it unique as long as possible.

For example if I\'m selecting a value 4 times from a array of 4 elements, the s

Answer 1

$isShowCategory = array();
for ($i=0; $i <5 ; $i++) { 
   $myCategory = array_rand($arrTrCategoryApp,1); 
   if (!in_array($myCategory, $isShowCategory)) {
      $isShowCategory[] = $myCategory;

      #do something 

   }
}