Answers for "displaya php erro"

show php erros

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1); 
error_reporting(E_ALL);

display php error

Only display php errors to the developer...

<?php
if($_SERVER['REMOTE_ADDR']=="00.00.00.00")
{
  ini_set('display_errors','On');
}
else
{
  ini_set('display_errors','Off');
}
?>

Just replace 00.00.00.00 with your ip address.