![](https://www.cnblogs.com/Emoticons/qface/055611161.gif)
对于input type='file'的值的清理方法如下:
function refreshUploader(who){
// pass who as argument,
// or who=document.getElementsByName('xx_file')[0];
var who2= who.cloneNode(false);
who2.onchange= who.onchange;// events are not cloned
who.parentNode.replaceChild(who2,who);
}