使用if-else条件在同一PHP中有多个头文件是否有效？

Question

if want a single PHP file to reirect to different pages according to different conditions say depending on the outcome of a post..

if(condition 1) {
    header("Location: page1.php");
    exit;
}
else if(condition 2) {
    header("Location: page2.php");
    exit;
}
else {
    header("Location: page3.php");
    exit;
}

Answer 1

Aboslutely!

You might want to make sure the headers haven't been sent first. You can use headers_sent for this

if (!headers_sent()) {
  // ...
}

A good way to handle this might be

function redirect_to($location) {
  if (headers_sent($filename, $line)) {
    trigger_error("Headers already sent in {$filename} on line {$line}", E_USER_ERROR);
  }
  header("Location: {$location}");
  exit;
}

// you can now use it like this
if(condition 1) {
  redirect_to("page1.php");
}
else if(condition 2) {
  redirect_to("page2.php");
}
else {
  redirect_to("page3.php");
}