Error when create array in php
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I have a sample code:

    $id = '1,2,3,4,5';
    $name = 'Iphone 3,Iphone 3S,Iphone 4,Iphone 4S,Iphone 5';
    $id_arr = array($id);
    $name_arr = array($name);
    $arr = array_combine($id_arr, $name_arr);
    print_r($arr);

When I `print_r($arr)` is result is `([1,2,3,4,5] =>'Iphone 3,Iphone 3S,Iphone 4,Iphone 4S,Iphone 5')`

How to fix this is the result `([1]=>'Iphone 3' [2] => 'Iphone 3S' ... [5]=>'Iphone 5')`