按钮在没有页面刷新的情况下一次浏览一个数组值

Question

I have a function that generates 10 random and unique numbers between 1-20.

function contain($prevItems, $number) {
            for ($k=0; $k<sizeof($prevItems); $k++) {
              if ($prevItems[$k] == $number)
                return true;
              }
              return false;
            }
            $num[0] = rand(1,20);
            $prevItems[0] = $num[0];
            for ($i=1; $i<=10; $i++) {
              $num[$i] = rand(1,10);
              while (contain($prevItems, $num[$i])) {
                $num[$i] = rand (1,20);
              }
              $prevItems[$i] = $num[$i];
           }
           sort($num);

I then have a button that fetches the first number from the array and echoes a text from database based on the number.

<form action="koe.php" method="POST">
<input id="myform" type="submit"  class="btn btn-primary" name="submit" value="new question">
</form

if(isset($_POST['submit'])) {
  if($result = $my->query("SELECT * FROM questions ORDER BY OID DESC LIMIT 1")) {
    if($result = $my->query('SELECT * FROM questions WHERE OID="'.$prevItems[0].'"')) {
      while($t = $result->fetch_object()) {
         echo '<h2>'.$t->text.'</h2>';
      }
    }
  }
}

My problem is this: I want the button to echo the next value from the previously. Like I want to echo prevItems[1] and then prevItems[2] without the page refresh because at the moment every time I press the button, the page refreshes and the function makes new 10 numbers so they're not unique anymore.

I've tried to stop page refresh with javascript

    var frm = $('#myform');
frm.submit(function (ev) {
    $.ajax({
        type: frm.attr('method'),
        url: frm.attr('action'),
        data: frm.serialize(),
        success: function (data) {
            alert('ok');
        }
    });

    ev.preventDefault();
});

I figured it can't work like this though but I'm not sure how to fix it.

To clarify: My problem is to go through array on a button click without page refresh. Everytime a button is pressed, the next number from array would show up. array[0] -> array[1] -> array[2] -> array[3]

Answer 1

I would change your php page to expect a post variable "num"

if(isset($_POST['num'])) {
  if($result = $my->query("SELECT * FROM questions ORDER BY OID DESC LIMIT     1")) {
    if($result = $my->query('SELECT * FROM questions WHERE     OID="'.$_POST['num'].'"')) {
      while($t = $result->fetch_object()) {
         echo '<h2>'.$t->text.'</h2>';
      }
    }
  }
}

//you probably want to google "mysql prevent injection" right after you get this working

Then in your ajax call you can pass in the "num"

$(function(){
  $("mybutton").on("click", function() {
    $.ajax({
     type: "POST",
     url: "myURL",
     data: { num:myNums[0] },
     success: function (data) {
            $("#output").innerHTML += data;
            myNums.splice(0,1); //take out the first num
        }
    });
  });
});