Change the digit format pagination in the slider

Question

There is a Swiper slider, now the pagination looks like 1 - 3, I need to be like that 01 - 03.

Here is a demo

https://codepen.io/anakin-skywalker94/pen/RmWxbE

HTML

<!-- Slider main container -->
<div class="swiper-container">
    <!-- Additional required wrapper -->
    <div class="swiper-wrapper">
        <!-- Slides -->
        <div class="swiper-slide">Slide 1</div>
        <div class="swiper-slide">Slide 2</div>
        <div class="swiper-slide">Slide 3</div>
    </div>
    <!-- If we need pagination -->
    <div class="swiper-pagination"></div>
</div>

JS

var swiper = new Swiper('.swiper-container', { 
      pagination: {
        el: '.swiper-pagination',
        type: 'fraction',
      },
      navigation: {
        nextEl: '.swiper-button-next',
        prevEl: '.swiper-button-prev',
      },
        direction: 'horizontal',
        loop: true,
        slidesPerView: 1,
        spaceBetween: 0,
        mousewheel: true,
        pagination: {
          el: '.swiper-pagination',
          type: 'fraction',
          clickable: true,

        renderFraction: function (currentClass, totalClass) {
        return '<span class="' + currentClass + '"></span>' + ' <span>-</span> ' + '<span class="' + totalClass + '"></span>'; }
        },

    });

Thanks!

Answer 1

Since the other answers no longer work, here is a working variant with a somewhat simplified structure and for the latest swiper version:

var swiper = new Swiper('.swiper-container', {
    effect: 'fade',
    pagination: {
        el: '.swiper-pagination',
        type: 'fraction',
        formatFractionCurrent: function (number) {
            return ('0' + number).slice(-2);
        },
        formatFractionTotal: function (number) {
            return ('0' + number).slice(-2);
        },
        renderFraction: function (currentClass, totalClass) {
            return '<span class="' + currentClass + '"></span>' +
                   ' - ' +
                   '<span class="' + totalClass + '"></span>';
        }
    },
});

.swiper-container {
    width: 100%;
    height: 100px;
}

.swiper-slide {
    text-align: center;
    font-size: 18px;
    background: #fff;
    background: gray;

    /* Center slide text vertically */
    display: -webkit-box;
    display: -ms-flexbox;
    display: -webkit-flex;
    display: flex;
    -webkit-box-pack: center;
    -ms-flex-pack: center;
    -webkit-justify-content: center;
    justify-content: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    -webkit-align-items: center;
    align-items: center;
}

<script src="https://unpkg.com/swiper/swiper-bundle.min.js"></script>
<link href="https://unpkg.com/swiper/swiper-bundle.min.css" rel="stylesheet"/>

<!-- Swiper -->
<div class="swiper-container">
  <div class="swiper-wrapper">
    <div class="swiper-slide">Slide 1</div>
    <div class="swiper-slide">Slide 2</div>
    <div class="swiper-slide">Slide 3</div>
    <div class="swiper-slide">Slide 4</div>
    <div class="swiper-slide">Slide 5</div>
    <div class="swiper-slide">Slide 6</div>
    <div class="swiper-slide">Slide 7</div>
    <div class="swiper-slide">Slide 8</div>
    <div class="swiper-slide">Slide 9</div>
    <div class="swiper-slide">Slide 10</div>
  </div>
  <!-- Add Pagination -->
  <div class="swiper-pagination"></div>
</div>

Answer 2

You can use something like ('0' + 4).slice(-2) in order to add the 0 in front of the numbers which are lower than 10 and higher than 0.

So your JS would look something like this:

var swiper = new Swiper('.swiper-container', { 
  pagination: {
    el: '.swiper-pagination',
    type: 'custom',
    renderCustom: function (swiper, current, total) {
      return ('0' + current).slice(-2) + ' of ' + ('0' + total).slice(-2);
    }
  },
  navigation: {
    nextEl: '.swiper-button-next',
    prevEl: '.swiper-button-prev',
  },
  direction: 'horizontal',
  loop: true,
  slidesPerView: 1,
  spaceBetween: 0,
  mousewheel: true,
    renderCustom: function (swiper, current, total) {
      return current + ' of ' + total;
  }
});

See the working Demo on codepen: https://codepen.io/Orlandster/pen/jobZmz