<form action="POST" enctype="multipart/form-data" >
<input type="file"  id="input__file">
<form>

var $input = $('#input__file');
    var fd = new FormData;

    fd.append('excel', $input.prop('files')[0]);
        $.ajax({
            url: '/center/ajax-file/',
            data: fd,
            processData: false,
            contentType: false,
            type: 'POST',
            success: function (data) {
              console.log(data)
            }
        });