JQuery Excel export issue

问题

I have some data from JQGrid that should be exported to excel. So, we have written a java servlet to write the data to excel and send it back. From the client side we are using an AJAX JSONP request by sending JSON data. I am able to hit the servlet and servlet sending the created excel back to the client. But i am not able to see excel or any kind of output from client side.

When i use the Fiddler and observed the http calls, i found that application received the result. but still it is not showing the result.

Here is my result header, that i have received.

HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Content-Disposition: attachment; filename=PistonData.xls
Content-Type: application/vnd.ms-excel
Content-Length: 6144
Date: Tue, 27 Mar 2012 08:49:04 GMT

How to open this result as Excel using JQuery? Can somebody please suggest me a way to fix this issue.

Update #1 Forgot to include request

$.ajax({
        type: "POST",
        dataType: "jsonp",
        contentType:'application/vnd.ms-excel',
        url: "http://devmachine:9010/axis/SPSServlet",
        data: param,
        success: function (dataToSend) {
            alert(dataToSend);
        }
    });

Update #2 As per Oleg's suggestions i worked out a solution for this problem.

Here is my code:

    <form id="frmExcelExport" style="display:none;">
       <input type=hidden id="partId" name="partId" />
       <input type=hidden id="columnNames" name="columnNames" />
       <input type=hidden id="data" name="data" />
    </form> 

$('#columnNames').val(colModStr);
$('#partId').val(currentPartID);
$('#data').val(dataStr);

var urlForExport = "http://devmachine:9010/axis/SPSServlet";        
$('#frmExcelExport').attr("method", "post");
$('#frmExcelExport').attr("action", urlForExport); 
$('#frmExcelExport').submit();

and it is working very good. Thanks a bunch to Oleg!!!!

回答1:

I think that you can't open Excel if you use HTTP POST. The way which will work is to use HTTP GET and encode parameters which you need in the URL:

window.location = "http://devmachine:9010/axis/StdPartSearchServlet?" +
    $.param({someParamName: "someValue", anotherParam: 123});

In the way the web browser will opens the returned data as PistonData.xls specified in Content-Disposition header with respect of the application registered for application/vnd.ms-excel (see Content-Type header). See the answer for more details.

If you need to prevent uncontrolled caching of the XLS data returned from the server I would recommend you to set additional HTTP header "Cache-Control: max-age=0" or better "Cache-Control: private, max-age=0" to prevent caching without re-validation on the HTTP proxy. See here, here for additional information.