sleep（）在php脚本中延迟整个页面

Question

I want to display the echo for 5 seconds and redirect the page to login.html but when the page loads it takes 5 seconds instead of loading the page and waiting 5 sec then redirect.

<?php

  session_start();
  if (isset($_SESSION['name'])) {
      echo $_SESSION['name'];
  } else {
      echo "Login To Order";
      sleep(5);
      echo "<script type=\"text/javascript\">
                window.location.href = \"login.html\"; 
            </script>";
  }

?>

EDIT: ok this seems to delay it for 5 seconds but the code execution still continues further but I want it to stop =>echo for 5 seconds =>redirect to the other page.

             echo "Login To Order"; 
             echo "<script type=\"text/javascript\">
                      window.setTimeout(function() {
                              window.location.href=\"login.html\";
                              }, 5000);
                     </script>";
            echo "this should not be displayed";

echo "this should not be displayed"; my point here is that I have others codes below that I don't want to be executed in the else case.

Answer 1

PHP pre-processes the page on the server, then sends the page to the client browser - sleeping on the server will rarely equate to a delay on the client

Put the delay on the client side using setTimeout

<?php
    session_start(); 
    if (isset($_SESSION['name'])){
        echo $_SESSION['name'];
    } else {
?>
        Login To Order
        <script>
            setTimeout(function() {
                window.location.href="login.html";
            }, 5000);
        </script>
<?php
        exit(0);
    }
?>

note how you can switch PHP preprocessing off ?> to make the script easier to write, then switch PHP back on <?php

or even simpler, use a HTTP header to do the work for you

<?php
    session_start(); 
    if (isset($_SESSION['name'])){
        echo $_SESSION['name'];
    } else {
        header("refresh:5; url=login.html"); 
?>
        Login To Order
<?php
        exit(0);
    }
?>