Javascript響應式圖片庫縮略圖

Question

我需要做一個響應式圖像縮略圖庫，我的當前看起來像這樣，您可以在代碼段中看到它。

由於必須顯示30張圖像，是否有一種方法可以使我的代碼更高效，從而不必一直重復圖像？

不幸的是，我無法使用插件，但可以自由使用jQuery。

你可以在這里檢查我的筆

我的HTML和CSS看起來像這樣：

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

您將不得不以一種或另一種方式使用圖像元素，因此這不應成為您的重點。 但是，當然您還可以采取其他措施來減少冗余，分離內容，表示形式和行為，並為自己提供更好的方式來隨着時間的流逝來擴展和調試頁面。

首先，不要將內聯樣式應用於元素，而應使用CSS選擇器來減少冗余並將內容與表示分離。

另外，雖然靜態HTML不會使用JavaScript運行時的任何功能，但是您可以自動化這些類的應用程序以及設置click事件處理程序（無論如何都不應使用內聯HTML事件處理屬性來完成）使用JavaScript。 這不會消除所有圖像元素，但是會減少該代碼的冗余。

其他幾件事...您的某些HTML無效，因為您的某些圖像元素沒有必需的alt屬性，無法為使用屏幕閱讀器軟件或看不到圖像的用戶提供替代文本描述。

最后，看起來您的許多圖像路徑在屬性值中都有一個尾隨空格。

 // 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>