javascript - 即使在javascript中的页面刷新时，如何保留范围 slider 的最后拖动位置

Question

我的网页由一个范围 slider 组成，该 slider 具有三个值 1,2,3，每个值都会在图像中发生变化，现在我的某个短语的要求是页面刷新，范围 slider 设置为我的值不想要它，我希望它即使在页面刷新时也能恢复其最后拖动的位置以及图像和短语我的 CSS 代码:

<style>
  .rangeslider {
    width: 50%;
    margin: 0 auto;
    position: absolute;
  }
  .myslider {
    -webkit-appearance: none;
    background: white;
    width: 100%;
    height: 20px;
    opacity: 0.8;
    margin-top: 180px;
  }
  .myslider::-webkit-slider-thumb {
    -webkit-appearance: none;
    cursor: pointer;
    background: #000080;
    width: 33%;
    height: 20px;
  }
  .myslider:hover {
    opacity: 1;
  }
  .image {
    position: relative;
    width: 400px;
    margin: 0 auto;
  }
  .image>img {
    position: absolute;
    display: none;
  }
  .image>img.visible,
  .image>img:first-child {
    display: block;
  }
  #sliderOutput>div {
    display: none;
  }
  #sliderOutput>div.visible,
  #sliderOutput>div:first-child {
    display: block;
  }
  </style>

我的 HTML 代码:

<div class="image mt-3 mb-3" id="sliderImages">
  <img src="/static/images/1.jpg" width="400" height="180"><!--Image1-->
  <img src="/static/images/2.jpg" width="400" height="180"><!--Image2-->
  <img src="/static/images/3.jpg" width="400" height="180"><!--Image3-->
</div><br><!-- End of Image sliding-->
<!--Range slider starts-->
<div class="rangeslider">
  <input type="range" min="1" max="3" value="1" class="myslider" id="sliderRange" onload="showVal(this.value)">

  <div class="container">
    <div id="sliderOutput">
      <div class="col-4" id="range_1">
        <h6 class="display-6 mt-3" ><b><center>Starting from scratch</center></b></h6>
        <p class="demo"><center>I'm designing the room </p>
      </div>
      <div class="col-4" id="range_2">
        <h6 class="display-6 mt-3"><b>Somewhere in Between</b></h6>
        <p class="demo">I'm designing around a few pieces I already own</p>
      </div>
      <div class="col-4" id="range_3">
        <h6 class="display-6 mt-3"><b>Mostly furnished</b></h6>
        <p class="demo">I want to put the finishing touches on my room</p>
      </div>
    </div><!--End of Range slider-->

我的Js代码:

window.onload = function()
{
  var imagePath = "../static/images/";
  var localStorageSliderNumber;
  var localStorageImagePath; 


  if (window.localStorage.getItem('sliderValue') != null) {
    localStorageSliderNumber = window.localStorage.getItem('sliderValue');
  } else {
    window.localStorage.setItem('sliderValue', '1');
    localStorageSliderNumber = 1;
  }
  if (window.localStorage.getItem('imagePath') != null) {
    imagePath = imagePath + window.localStorage.getItem('imagePath') + ".jpg";
  }
  var rangeslider = document.getElementById("sliderRange");
  var output = document.getElementById("sliderOutput");
  var images = document.getElementById("sliderImages");

  rangeslider.addEventListener('input', function() {
    for (var i = 0; i < output.children.length; i++) {
      output.children[i].style.display = 'none';
      images.children[i].style.display = 'none';
    }
    i = Number(this.value) - 1;
    output.children[i].style.display = 'block';
    images.children[i].style.display = 'block';
    window.localStorage.setItem('imagepath', rangeslider.getAttribute('value'));
    window.localStorage.setItem('sliderValue', (i+1));


});
}

在这里，我将值存储在本地存储中，即 slidervalue，但现在我想保留范围 slider 的最后拖动位置以及短语和图像

       [1]: https://codepen.io/lakshmi123__/pen/abzYeLP

Answer 1

给你。

您只需要在加载时调用 setter 方法即可。我所做的是，我分离了用于单独设置数据的通用代码，并在加载和值更改时调用它。这是更新后的代码。

window.onload = function() {
  var imagePath = "../static/images/";
  var localStorageSliderNumber;
  var localStorageImagePath;
  if (window.localStorage.getItem('sliderValue') != null) {
    localStorageSliderNumber = window.localStorage.getItem('sliderValue');
  } else {
    window.localStorage.setItem('sliderValue', '1');
    localStorageSliderNumber = 1;
  }
  if (window.localStorage.getItem('imagePath') != null) {
    imagePath = imagePath + window.localStorage.getItem('imagePath') + ".jpg";
  }
  var rangeslider = document.getElementById("sliderRange");
  var output = document.getElementById("sliderOutput");
  var images = document.getElementById("sliderImages");
  rangeslider.value = localStorageSliderNumber;
  //The common line of code extracted into a method
  setData(rangeslider, output, images, localStorageSliderNumber);
  rangeslider.addEventListener('input', function() {
    //call the method once again
    setData(rangeslider, output, images, this.value);
  });
}

function setData(rangeslider, output, images, value) {
  for (var i = 0; i < output.children.length; i++) {
    output.children[i].style.display = 'none';
    images.children[i].style.display = 'none';
  }
  i = Number(value) - 1;

  output.children[i].style.display = 'block';
  images.children[i].style.display = 'block';
  window.localStorage.setItem('imagepath', rangeslider.getAttribute('value'));
  window.localStorage.setItem('sliderValue', (i + 1));
  window.localStorage.setItem('sliderPosition', (i + 1))
}

这是Updated Pen