Javascript响应式图片库缩略图

Question

我需要做一个响应式图像缩略图库，我的当前看起来像这样，您可以在代码段中看到它。

由于必须显示30张图像，是否有一种方法可以使我的代码更高效，从而不必一直重复图像？

不幸的是，我无法使用插件，但可以自由使用jQuery。

你可以在这里检查我的笔

我的HTML和CSS看起来像这样：

HTML：

<h2 style="text-align:center">Lightbox</h2>

<div class="row">
  <div class="column">
    <img src="https://placehold.it/180x180.jpg " style="width:100%" onclick="openModal();currentSlide(1)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="https://placehold.it/180x180.jpg " style="width:100%" onclick="openModal();currentSlide(2)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="https://placehold.it/180x180.jpg " style="width:100%" onclick="openModal();currentSlide(3)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="https://placehold.it/180x180.jpg " style="width:100%" onclick="openModal();currentSlide(4)" class="hover-shadow cursor">
  </div>
</div>

<div id="myModal" class="modal">
  <span class="close cursor" onclick="closeModal()">&times;</span>
  <div class="modal-content">

    <div class="mySlides">
      <div class="numbertext">1 / 4</div>
      <img src="https://placehold.it/180x180.jpg " style="width:100%">
    </div>

    <div class="mySlides">
      <div class="numbertext">2 / 4</div>
      <img src="https://placehold.it/180x180.jpg " style="width:100%">
    </div>

    <div class="mySlides">
      <div class="numbertext">3 / 4</div>
      <img src="https://placehold.it/180x180.jpg " style="width:100%">
    </div>

    <div class="mySlides">
      <div class="numbertext">4 / 4</div>
      <img src="https://placehold.it/180x180.jpg " style="width:100%">
    </div>

    <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
    <a class="next" onclick="plusSlides(1)">&#10095;</a>

    <div class="caption-container">
      <p id="caption"></p>
    </div>


    <div class="column">
      <img class="demo cursor" src="https://placehold.it/180x180.jpg " style="width:100%" onclick="currentSlide(1)" alt="Nature and sunrise">
    </div>
    <div class="column">
      <img class="demo cursor" src="https://placehold.it/180x180.jpg " style="width:100%" onclick="currentSlide(2)" alt="Trolltunga, Norway">
    </div>
    <div class="column">
      <img class="demo cursor" src="https://placehold.it/180x180.jpg " style="width:100%" onclick="currentSlide(3)" alt="Mountains and fjords">
    </div>
    <div class="column">
      <img class="demo cursor" src="https://placehold.it/180x180.jpg " style="width:100%" onclick="currentSlide(4)" alt="Northern Lights">
    </div>
  </div>
</div>

CSS：

body {
  font-family: Verdana, sans-serif;
  margin: 0;
}

* {
  box-sizing: border-box;
}

.row > .column {
  padding: 0 8px;
}

.row:after {
  content: "";
  display: table;
  clear: both;
}

.column {
  float: left;
  width: 25%;
}

/* The Modal (background) */
.modal {
  display: none;
  position: fixed;
  z-index: 1;
  padding-top: 100px;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: black;
}

/* Modal Content */
.modal-content {
  position: relative;
  background-color: #fefefe;
  margin: auto;
  padding: 0;
  width: 90%;
  max-width: 1200px;
}

/* The Close Button */
.close {
  color: white;
  position: absolute;
  top: 10px;
  right: 25px;
  font-size: 35px;
  font-weight: bold;
}

.close:hover,
.close:focus {
  color: #999;
  text-decoration: none;
  cursor: pointer;
}

.mySlides {
  display: none;
}

.cursor {
  cursor: pointer
}

/* Next & previous buttons */
.prev,
.next {
  cursor: pointer;
  position: absolute;
  top: 50%;
  width: auto;
  padding: 16px;
  margin-top: -50px;
  color: white;
  font-weight: bold;
  font-size: 20px;
  transition: 0.6s ease;
  border-radius: 0 3px 3px 0;
  user-select: none;
  -webkit-user-select: none;
}

/* Position the "next button" to the right */
.next {
  right: 0;
  border-radius: 3px 0 0 3px;
}

/* On hover, add a black background color with a little bit see-through */
.prev:hover,
.next:hover {
  background-color: rgba(0, 0, 0, 0.8);
}

/* Number text (1/3 etc) */
.numbertext {
  color: #f2f2f2;
  font-size: 12px;
  padding: 8px 12px;
  position: absolute;
  top: 0;
}

img {
  margin-bottom: -4px;
}

.caption-container {
  text-align: center;
  background-color: black;
  padding: 2px 16px;
  color: white;
}

.demo {
  opacity: 0.6;
}

.active,
.demo:hover {
  opacity: 1;
}

img.hover-shadow {
  transition: 0.3s
}

.hover-shadow:hover {
  box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19)
}

Answer 1

您将不得不以一种或另一种方式使用图像元素，因此这不应成为您的重点。 但是，当然您还可以采取其他措施来减少冗余，分离内容，表示形式和行为，并为自己提供更好的方式来随着时间的流逝来扩展和调试页面。

首先，不要将内联样式应用于元素，而应使用CSS选择器来减少冗余并将内容与表示分离。

另外，虽然静态HTML不会使用JavaScript运行时的任何功能，但是您可以自动化这些类的应用程序以及设置click事件处理程序（无论如何都不应使用内联HTML事件处理属性来完成）使用JavaScript。 这不会消除所有图像元素，但是会减少该代码的冗余。

其他几件事...您的某些HTML无效，因为您的某些图像元素没有必需的alt属性，无法为使用屏幕阅读器软件或看不到图像的用户提供替代文本描述。

最后，看起来您的许多图像路径在属性值中都有一个尾随空格。

 // Place all of this code into a <script></script> element and place that element // just before the closing of the <body> element (</body>) so that by the time // the script is reached, all the HTML will have already been parsed into memory. // Get references to the elements you need to work with: var prev = document.querySelector(".prev"); var next = document.querySelector(".next"); var close = document.querySelector(".close"); // Get a node list of the sets of images and turn the node list into a proper array var columnImages1 = Array.prototype.slice.call(document.querySelectorAll("div.row > div.colum > img.hover-shadow.cursor")); var columnImages2 = Array.prototype.slice.call(document.querySelectorAll("div.column > img.demo")); // Loop over the first group of images and set up their click event handlers columnImages1.forEach(function(img, index){ img.addEventListener("click", function(){ openModal(); currentSlide(index + 1); }); }); // Loop over the second group of images and set up their click event handlers columnImages1.forEach(function(img, index){ img.addEventListener("click", function(){ currentSlide(index + 1); }); }); // Set up the click event handler for the close, previous and next buttons close.addEventListener("click", closeModal); prev.addEventListener("click", function(){ plusSlides(-1) }); next.addEventListener("click", function(){ plusSlides(1) }); 

 * { box-sizing: border-box; } body { font-family: Verdana, sans-serif; margin: 0; } /* This will eliminate the need to repeat "width:100%" on all your slides */ .mySlides > img, .column > img { width: 100%; } .row > .column { padding: 0 8px; } .row:after { content: ""; display: table; clear: both; } .column { float: left; width: 25%; } /* The Modal (background) */ .modal { display: none; position: fixed; z-index: 1; padding-top: 100px; left: 0; top: 0; width: 100%; height: 100%; overflow: auto; background-color: black; } 

 <h2 style="text-align:center">Lightbox</h2> <div class="row"> <div class="column"> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here" class="hover-shadow cursor"> </div> <div class="column"> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here" class="hover-shadow cursor"> </div> <div class="column"> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here" class="hover-shadow cursor"> </div> <div class="column"> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here" class="hover-shadow cursor"> </div> </div> <div id="myModal" class="modal"> <span class="close cursor">&times;</span> <div class="modal-content"> <div class="mySlides"> <div class="numbertext">1 / 4</div> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here"> </div> <div class="mySlides"> <div class="numbertext">2 / 4</div> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here"> </div> <div class="mySlides"> <div class="numbertext">3 / 4</div> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here"> </div> <div class="mySlides"> <div class="numbertext">4 / 4</div> <img src="https://placehold.it/180x180.jpg" alt="You need a short description here"> </div> <a class="prev">&#10094;</a> <a class="next">&#10095;</a> <div class="caption-container"> <p id="caption"></p> </div> <div class="column"> <img class="demo cursor" src="https://placehold.it/180x180.jpg" alt="Nature and sunrise"> </div> <div class="column"> <img class="demo cursor" src="https://placehold.it/180x180.jpg" alt="Trolltunga, Norway"> </div> <div class="column"> <img class="demo cursor" src="https://placehold.it/180x180.jpg" alt="Mountains and fjords"> </div> <div class="column"> <img class="demo cursor" src="https://placehold.it/180x180.jpg" alt="Northern Lights"> </div> </div> </div>