<script type="text/javascript">  
    function fun() {   
        var oImg = document.createElement('img');   
        oImg.src = "/inc/4.jpg";   
        document.getElementById('test').appendChild(oImg);  
       // document.getElementById('pic').value="/inc/4.jpg";
    }   

function check(){

 document.getElementById('pic').value=document.getElementById('test').innerHTML;
}
</script>  
 
<form name="form1" method="post" action="test.html" onSubmit="check();">
  <textarea name="test" cols="50" rows="20" id="test">ddddddddd</textarea>
  <img src="/inc/4_s.jpg" onClick="fun()" value="fun">
<input type="hidden" name="pic" id="pic">
<input type="submit" name="button" id="button" value="提交">
</form>

• textarea