jquery jqXHR.getResponseHeader(‘Location’)为null

$.ajax({
                url: VIDEOS_UPLOAD_serviCE_URL,method: 'POST',contentType: 'application/json',headers: {
                    Authorization: 'Bearer ' + accessToken,'x-upload-content-length': file.size,'x-upload-content-type': file.type
                },data: JSON.Stringify(Metadata)
            }).done(function(data,textStatus,jqXHR) {
                resumableUpload({
                    url: jqXHR.getResponseHeader('LOCATIOn'),file: file,start: 0
                });
            });