删除PHP中的select选项（带会话）

I have a problem with the unset of my session because I've done it on a function and only the internal parameter delete the select value id.

Have a look:

/***
 * @name DeleteItem
 * @date 04.10.2014
 * @param   The array that contains the element to delete
 * @param   The id of the selected index
 * @param   The name of the button that start the delete
 * @version 1.0
 * @description Delete an item to the select
 */

function DeleteItem($array,$SelectID,$btnDelete) {
    //The delete button was clicked?
    if(isset($_POST[$btnDelete]))
    {
    //Find the element with the id and delete the value
    foreach ($array as $idx =>$value)
    {
        if ($idx == $SelectID)
        {
             unset($array,$SelectID);
        }
    }
    return $array;
    } 

Thanks - I'm sure that it's something really simple to do.

Finally found was just a question of references values(i was working whith copy) I just add a & before function

Your unset() syntax is wrong for the type of operation you are trying to do. You want to delete only index $SelectID from array. Try below code:

unset($array[$SelectID]);

Also, you don't need the loop. Below is a simplified version:

function DeleteItem($array,$SelectID,$btnDelete) {
   //The delete button was clicked? and if index exists in array
   if(isset($_POST[$btnDelete]) && array_key_exists($SelectID, $array)) {
         unset($array[$SelectID]);
   }
   return $array;
}

And, you need to delete (call DeleteItem()) only if the POST variable exists. So, you can further simplify as below and remove isset($_POST[$btnDelete]) from if condition:

if(isset($_POST[$btnDelete])) {
   DeleteItem($array,$SelectID);
}

You are using 'unset' incorrectly.

If $SelectID is a value of the array,

$index = array_search($SelectID, $array);
if ($index) {
  unset($array[$index]);
}

or, if the $SelectID is 'key' of the array & not a value, then...

$keys = array_keys($array);
$index = array_search($SelectID, $keys);
if (!empty($keys[$index])) {
   unset($array[$keys[$index]]);
}
print_r($array);

(Pss: we don't need a foreach)