模内Ajax文件上传

I have no idea how to implement this, let me try to explain

I have a form that open inside a bootstrap modal frame in my layout, in this form i have 2 fields

<input type="file" name="photoimg" id="photoimg" value="" />
<input type="hidden" name="consulta" value="5">

I need to submit this to my url with the value 5 for 'consulta' so the script can read and do the proper things with the file,

BUT

I need to do this without refreshing the opened modal, in other words, using ajax to submit the file (for further cropping)

i have this script that do the submit, what i'm doing wrong here?

<script type="text/javascript">
                    function enviaimagem(){

                        $.ajax({
                            type: "POST",
                            data: { consulta:5 },
                            dataType: 'html',
                            url: "<?=JURI::ROOT()?>ajax.html",
                    //dataType: "html",
                    success: function(result){
                        $("#corpo_modal").html('');
                        $("#corpo_modal").html(result);
                    },
                    beforeSend: function(){
                        $("#corpo_modal").html('');
                        $("#corpo_modal").css({display:"none"});
                        $('#ajaxloadergeneric').css({display:"block"});
                    },
                    complete: function(msg){
                        $('#ajaxloadergeneric').css({display:"none"});
                        $("#corpo_modal").css({display:"block"});
                    }
                    });
                }
                </script>

File upload through AJAX is supported through FormData object:

https://developer.mozilla.org/en-US/docs/Web/Guide/Using_FormData_Objects

, however it is not supported by all/old browsers( especially IE < 10)