使用ajax帖子上传文件而不刷新页面

Question

I have a page file-upload.jsp with the code snippet below:

 <form action="" id="frmupload" name="frmupload" method="post" enctype="multipart/form-data">
     <input type="file" id="upload_file" name="upload_file" multiple="" />
     <input type="submit" value="Update" />
 </form>

I have 2 questions:

1. The moment I select some files, ie the onchange event of the input type file , the file(s) should get uploaded.

   I have a Java page that receives multipart request parameter and uploads the file to the said location. My problem is the form submission onchange , so that the Java file can proceed with further operations.

   I googled and went through lot of articles. Some say it's not possible to upload files directly via Ajax, some say submit the form to an iframe via Ajax/jQuery.

   I tried a lot of code from internet, such as this:

    $(document).ready(function(){ $('upload_file').change(function(){ var data = new FormData(); data.append('file', $(this[0].files[0])); $.ajax({ url: 'photo.jsp', type: 'post', contentType: attr('enctype', "multipart/form-data"), data: data, success: function(data){ alert(data); } }) }); }); 

   but could not get the expected results.

2. I also need a progress bar for the upload operation.

Answer 1

Look at this example using an IFrame, is in PHP but changing the action should do the trick

Ajax Style File Uploading Using Hidden IFrame

Answer 2

Since you're already using jQuery, I would definitely go for the jQuery Form Plugin , which allows you to do form uploads via AJAX, even if the form contains a file input.

There is an example on its website available that shows how to display a progress bar.

Answer 3

Look at this example it is exact as you want

http://www.asp.net/ajaxlibrary/ajaxcontroltoolkitsamplesite/asyncfileupload/asyncfileupload.aspx