struts2 - How to upload files using java? -

the scenario follows,

user clicks on upload images, 3 upload file fields shown upload 3 images, there button add more images, user can upload unlimited number of images clicking on button show more upload file fields, not sure how implement this. there many examples none of them upload more images feature.

i have following code not sure how implement button upload more images

<s:form action="uploadimages" method="post" encytype="multipart/form-data">         <s:file label="file 1" name="fileupload"/>         <s:file label="file 2" name="fileupload"/>         <s:file label="file 3" name="fileupload"/>         <s:submit value="submit" name="upload"/>     </s:form> 

that not difficult.

inside javascript, keep track of counter value starting counter = 0

create first upload field as:

<input type="file" name="file[0]">

whenever user clicks 'upload more images...', use javascript increment counter, append new file input field:

<input type="file" name="file[1]">

and on...

<input type="file" name="file[2]"> <input type="file" name="file[3]"> <input type="file" name="file[4]"> <input type="file" name="file[5]"> 

when submit form, images submitted server, , can use loop process each uploaded image 1 one.

to add new file input field quickly, recommend using jquery. first, set id on form seen below:

<s:form id="myform" action="uploadimages" method="post" encytype="multipart/form-data">     <s:file label="file 1" name="file[0]"/>     <s:file label="file 2" name="file[1]"/>     <s:file label="file 3" name="file[2]"/>     <s:submit value="submit" name="upload"/> </s:form> 

then, add new input field this:

<script type="text/javascript">     var counter = 3;      function onaddmorebuttonclicked() {         (var = 0; < 3; i++) {             $("#myform").append($("<input>").attr({"type" : "file", "name" : "file["+counter + "]"}));             counter = counter + 1;         }     } </script>