PHP rename the keys of an array

Question

How can I rename keys in an array?

Start with this array named $start_array,

[0] => 
      [date] => 2012-05-01
      [revenue] => 100
[1]          


        

Answer 1

foreach( $start_array as &$arr ) {
  $arr["x"] = $arr['date'];
  unset( $arr['date'] );
  $arr['y'] = $arr['revenue'];
  unset( $arr['revenue'] );
}
unset($arr);

Try the above code.