js实现限制上传文件大小

<html>   
<head>   
<script type="text/javascript">   
  var isIE = /msie/i.test(navigator.userAgent) && !window.opera;         
  function fileChange(target) {     
      
    var fileSize = 0;          
    if (isIE && !target.files) {      
      var filePath = target.value;      
      var fileSystem = new ActiveXObject("Scripting.FileSystemObject");         
      var file = fileSystem.GetFile (filePath);      
      fileSize = file.Size;     
    } else {     
     fileSize = target.files[0].size;      
     }    
     var size = fileSize / 1024;     
     if(size>10000){   
      alert("附件不能大于10M");   
        
        
     }   
       
}    
</script>   
</head>   
<body>   
<input type="file" name="contractFileName"  style="width: 500px;" onchange="fileChange(this);"/>   
</body>   
</html>  

  

posted @ 2015-09-10 14:40  Rain-Heart  阅读(2440)  评论(0编辑  收藏  举报