html,css,js实现Upload 上传

实现效果：

代码实现：

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link rel="stylesheet" href="./font_4718460_gwu8lpmmfps/iconfont.css">
  <style>
    *{
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    /* a{
      text-decoration: none;
      color: #606266;
      font-size: 14px;
    } */
    .upload{
      padding: 20px 10px;
    }
    input{
      display: none;
    }
    label{
      display: block;
      width: 80px;
      height: 30px;
      background-color: #409eff;
      color: #fff;
      text-align: center;
      font-size: 12px;
      line-height: 30px;
      border-radius: 5px;
    }
    .upload-tip{
      padding: 5px 0;
      font-size: 12px;
      color: #606266;
    }
    .upload-message li{
      cursor: pointer;
      position: relative;
      height: 30px;
      width: 400px;
      padding: 5px 0 5px 18px;
      color: #606266;
    }
    li::before{
      content: '';
      position: absolute;
      top: 8px;
      left: 0;
      width: 14px;
      height: 14px;
      background-image: url(./image/文件.png);
      background-size: cover;
    }
    li .close{
      content: '';
      position: absolute;
      top: 8px;
      right: 5px;
      width: 14px;
      height: 14px;
      background-image: url(./image/对号.png);
      background-size: cover;
    }
    .upload-message li:hover .close{
      background-image: url(./image/取消.png); 
    }
    .upload-message li:hover{
      background-color: #f5f7fa;
      color: #409eff;
    }
  </style>
</head>
<body>
  <div class="upload">
    <label><input type="file" id="file-upload">点击上传</label>
    <p class="upload-tip">只能上传jpg/png文件，且不超过500kb</p>
    <ul class="upload-message">
      <!-- <li>'55555555' <span class="close"></span></li> -->
    </ul>
  </div>
  <script>
    const inp=document.querySelector('#file-upload')
    const upmessages=document.querySelector('.upload-message')
    inp.addEventListener('change',function(e){
      console.log(e.target.files[0]);//文件名

      // 1.文件大小
      const file=e.target.files[0]
      // 500kb转换为字节
      if(file.size > 500 * 1024 ){
        alert('文件大小不能超过500kb')
        return
      }

      // 2.文件类型
      if(!file.type.match('image/jpg') && !file.type.match('image/png')){
        alert('只能上传jpg/png文件')
        return
      }

      // 3.添加文件到页面
      const newli=document.createElement('li')
      newli.innerHTML=file.name + '<span class="close"></span>'
      upmessages.appendChild(newli)
      // 4.点击删除
      const closes=document.querySelectorAll('.close')
      closes.forEach(item=>{
        item.addEventListener('click',function(e){
          const content=e.target.parentElement
          upmessages.removeChild(content)
        })
      })
    })
  </script>
</body>
</html>