主要是定位和不透明度来实现：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Document</title> <style> /*a upload */ .a-upload { padding: 4px 10px; height: 20px; line-height: 20px; position: relative; cursor: pointer; color: #888; background: #fafafa; border: 1px solid #ddd; border-radius: 4px; overflow: hidden; display: inline-block; *display: inline; *zoom: 1 } .a-upload input { position: absolute; font-size: 100px; right: 0; top: 0; opacity: 0; filter: alpha(opacity=0); cursor: pointer } .a-upload:hover { color: #444; background: #eee; border-color: #ccc; text-decoration: none } .file { position: relative; display: inline-block; background: #D0EEFF; border: 1px solid #99D3F5; border-radius: 4px; padding: 4px 12px; overflow: hidden; color: #1E88C7; text-decoration: none; text-indent: 0; line-height: 20px; } .file input { position: absolute; font-size: 100px; right: 0; top: 0; opacity: 0; } .file:hover { background: #AADFFD; border-color: #78C3F3; color: #004974; text-decoration: none; } </style> </head> <body> <a href="javascript:;" class="a-upload"> <input type="file" name="">点击这里上传文件 </a> <a href="javascript:;" class="file">选择文件 <input type="file" name=""> </a> </body> </html>