确保每个用户的点击仅在定义的时间段内发送一次

Hi I have the following code which I am trying to adapt to make sure that when Like is clicked by a user who is logged in, then only one request is sent in a predetermined period of time that can be adjusted i.e Like can be clicked and a request sent only once every 5 minutes. There must be a javascript function I can use but I can't figure it out.

index.php:

<?php
  include 'init.php';
  include 'connect.php';
?>
<!doctype html>
  <html>
    <body>
      <?php       
        $userid = $_SESSION['user_id'];
        echo '<a class="like" href="#" onclick="like_add(', $userid,');">Like</a>';
      ?>
      <script type ="text/javascript" src="jquery-1.11.1.min.js"></script>
      <script type ="text/javascript" src="like.js"></script>      
  </body>
</html>

connect.php:

<?php  
  $servername = "localhost";
  $username = "root";
  $password = "";
  $dbname = "DB";
  $conn = new mysqli($servername, $username, $password, $dbname);

  if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
  }
?>

init.php:

<?php
  session_start();
  $_SESSION['user_id']='1';
  $userid = $_SESSION['user_id'];
  include 'connect.php';
  include 'like.php';
?>

like.js:

function like_add(userid) {
  $.post('like_add.php', {userid:userid}, function(data) {
    if (data == 'success'){
      add_like($userid);
    } else {
      alert(data);
    }
  });
}

like.php:

<?php
  function add_like($userid) {
    include 'connect.php';

    $stmt = $conn->prepare("INSERT INTO clicks (user) VALUES (?)");
    $stmt->bind_param("s", $userid);

    $stmt->execute();
    $stmt = $conn->prepare("SELECT max(id) FROM clicks WHERE user=?");
    $stmt->bind_param("s", $userid);
    $stmt->execute();
    $stmt->bind_result($click);
    $stmt->fetch();
    echo $click;
    $stmt->close();
  }
?

like_add.php

<?php
  include 'init.php';
  if (isset($userid)) {
    $userid = $userid;
    add_like($userid);
  }
?>

If you pass the a tag into like_add like so:

<?php       
    $userid = $_SESSION['user_id'];
    echo '<a class="like" href="#" onclick="like_add(this, '.$userid.');">Like</a>';
?>

You can disable it in the javascript function for a set time period:

function like_add(a, userid) {
    a.disabled = true;
    setTimeout(function(){
         a.disabled = false;
    ), 5000});//Code will execute in 5 seconds to enable the a tag

    $.post('like_add.php', {userid:userid}, function(data) {
        if (data == 'success'){
            add_like($userid);
        }else{
            alert(data);
        }
    });
}

Is this something alogn the lines of what you were looking for?

In a completly not recommended way, you could define

var isLikeable = true;

function likeStatus(secs) {
  isLikeable = false;
  window.setTimeout("isLikeable = true;", (secs*60));
}

then, when clicking the "like" you would check

if (isLikeable) { // do like and call likeStatus(300); }

Do you need this to be enforced on the back-end, or is disabling it through the UI sufficient? You could theoretically get people hacking it using Developer tools or Firebug, but this seems very unlikely from casual users.

On the front end, I would user jQuery to add code on the click event that disables the "Like" button with a timeout, like this:

// First, move your click handler to your script file
$('.like').click( function(event) {
   // Make sure clicking the button doesn't submit any form context that might be present
   event.preventDefault();

   var DURATION_IN_MINUTES = 5;

   // Grab the user id that will be added as an attribute of your element: data-user-id="$userid"
   var user_id = $(this).data('userID');

   // Run your function
   like_add(user_id);

   // Disable clicking like (it's easiest to do this with a button, by far
   $(this).prop({'disabled':true,'title':'Disabled for ' + DURATION_IN_MINUTES + ' minutes');

   // Set a timer to re-enable the like button in 5 minutes
   setTimeout( function() { $(this).prop({'disabled':false,'title':''}), DURATION_IN_MINUTES * 60 * 1000}
});

and then in your HTML:

echo '<a class="like" href="#" onclick="like_add(', $userid, ');">Like</a>';

becomes

echo '<button class="like" data-user-id="' + $userid + '">Like</button>';

I don't have a PHP environment to test this (and I haven't tested the JavaScript itself, to be honest), but this should be enough to get you started.

If you want to block multiple submissions on the back-end, you'll want to timestamp your likes, and do a look-up to see the last time a given user "liked" that link.