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JS实现图片预加载之无序预加载功能代码

2019-11-19 16:35:42
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图片预加载之无序预加载的效果图如下所示,如果大家感觉不错,请参考实现代码。

具体代码如下所示:

<!DOCTYPE html><html lang="zh-CN"><head>  <meta charset="UTF-8">  <title>PreLoading</title>  <style>    *{margin:0; padding:0; border:none; outline:0; text-decoration:none;}    html,body,.box{width:100%; height:100%;}    .box{display:none;}    #img{width:90%; height:90%; margin:2vh auto 0; display:block; box-shadow:0 0 10px gray;}    .box .btns{width:140px; height:40px; display:block; margin:20px auto;}    .box .btns .btn{width:60px; height:40px; display:block; border:1px gray solid; background-color:#ccc; text-align:center; line-height:40px; float:left;}    .box .btns .btn:nth-of-type(2){margin-left:16px;}    .load{width:100%; height:100%; display:block; font-size:60px; font-family:"微软雅黑"; color:#ccc; text-align:center; line-height:100vh; position:fixed;}  </style></head><body>  <div class="box">    <img id="img" src="" alt="pic">    <p class="btns"><a href="javascript:" rel="external nofollow" rel="external nofollow" class="btn">prev</a><a href="javascript:" rel="external nofollow" rel="external nofollow" class="btn">next</a></p>  </div>  <p class="load">0%</p>  <script type="text/javascript">    var imgs = ['http://down.699pic.com/photo/50036/7661.jpg?_upt=da51378d1494571758&_upd=500367661.jpg',          'http://desk.fd.zol-img.com.cn/t_s1920x1080c5/g5/M00/09/0F/ChMkJljskIqIPX9bAAMPyuIn8DcAAbj8QB7XpYAAw_i343.jpg',          'http://desk.fd.zol-img.com.cn/t_s1920x1080c5/g5/M00/09/0F/ChMkJljskLeIaW-JAAIudN_yqvgAAbj8gDQO5AAAi6M64.jpeg',          'http://desk.fd.zol-img.com.cn/t_s1920x1080c5/g5/M00/0F/08/ChMkJlauzISIH0uXAARUHuJLVX8AAH8-gHu6zsABFQ2166.jpg',          'http://desk.fd.zol-img.com.cn/t_s1920x1080c5/g5/M00/0F/08/ChMkJlauzISIIL5TAAObxg4-XeUAAH8-gHzP3EAA5ve000.jpg'];    // 绑定按钮事件    var btns = document.getElementsByClassName('btn'),      img = document.getElementById('img'),      index = 0;    for(var i=0;i<btns.length;i++){      btns[i].onclick = function(){        if(this.innerHTML === 'next'){          index = Math.min(++index , imgs.length-1);          img.setAttribute('src',imgs[index]);        }        if(this.innerHTML === 'prev'){          index = Math.max(--index , 0);          img.setAttribute('src',imgs[index]);        }      }    }    // 计数变量    var count = 0,      load = document.getElementsByClassName('load')[0],      box = document.getElementsByClassName('box')[0];    // 无序预加载    for(var i=0;i<imgs.length;i++){      (function(i){        var imgObj = new Image();      imgObj.onload = function(){          load.innerHTML = Math.round((count + 1) / imgs.length * 100) + '%';          count++;          if(count >= imgs.length-1){            load.style.display = 'none';            box.style.display = 'block';            img.setAttribute('src',imgs[0]);            document.title = '1/' + imgs.length;          }        }      imgObj.onerror = function(){          load.innerHTML = Math.round((count + 1) / imgs.length * 100) + '%';          count++;          if(count >= imgs.length-1){            load.style.display = 'none';            box.style.display = 'block';            img.setAttribute('src',imgs[0]);            document.title = '1/' + imgs.length;          }        }        imgObj.src = imgs[i];      })(i);    }  </script></body></html>

以上所述是小编给大家介绍的JS实现图片预加载之无序预加载功能代码,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对武林网网站的支持!

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