JS获取GIF帧数并限制上传的实现方案

基于libgif-js的代码实现

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title></title>
    <meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" />
    <style type="text/css">
      *{
        padding: 0;
        margin: 0;
        box-sizing: border-box;
      }
   
    </style>
  </head>
  <body>
    <input type="file" name="file" id="file" value="" />
     
  </body>
  <script type="text/javascript" src="js/libgif.js"></script>
  <script type="text/javascript">
 
    document.getElementById("file").onchange = function(e){
      var filse = this.files;
      sendFile(filse[0]);
    }
    function sendFile(file){ 
      var reader =new FileReader();
      reader.readAsDataURL(file);
      reader.onload=function(e){
        var div = document.createElement("div");
        var img = document.createElement("img");
        div.appendChild(img);
        img.src = this.result;
        img.onload = function(){
          var rub = new SuperGif({ gif: img} );
          rub.load(function(){
            console.log(rub.get_length());
             
          });
        }
      }
    }
  </script>
</html>