Submit HTML Form from JQuery

<input id="BrId" name="BrId" type="text" value="1">

<!-- HTML Form- -->
<form id="photoform" enctype="multipart/form-data" method="post" action="server-side-path">
    <input type="file" id="Photos" name="photo"/>
    <input type="hidden" name="VisitGuid" value="5" />
    <input type="hidden" name="HiddenBrId" id="HiddenBrId" value="" />
    <input type="submit" name="submit_btn" />
</form>
<script>
$('#photoform').on('submit', function (e) { 
     e.preventDefault();
     $('#HiddenBrId').val($('#BrId').val());
     $('#photoform')[0].submit();
});
</script>