onclick시 추가되는 스크립트

function addImage() {

var num = document.all["userfile[]"].length;

if(num != "undifined" && num == 10) {

alert("첨부파일은 10개까지 가능합니다");

return;

}

attach_file.innerHTML += '<input type="file" size="60" name="userfile[]" class="input"><br>';

}

<input type="file" size="60" name="userfile[]" id="userfile1" class="input" /> &nbsp;

<input type="button" onclick="addImage();" onmouseover="toggleBtn(this, 1);" onmouseout="toggleBtn(this, 0);" value="파일추가" class="butt" /> 

<div id="attach_file"></div>