nodejs jquery下载本地文件 webstorm

$("#downloadTest").click(function() {
$('#hidden_iframe').remove();
var iframe = $('<iframe id="hidden_iframe" style="display:none;"></iframe>');
var form = $('<form></form>')
.attr('target','hidden_iframe')
.attr('action','/service/downloadFile')
.attr('method', 'get');

var input = $('<input />').attr('name','fileName').attr('value', '@fileName').appendTo(form);
iframe.append(form).appendTo(document.body);
iframe.on('load', function() {
window.reload();
})
$(form).submit();
})

var path = require('path');
exports.download = function(req, res) {
var paths = path.join('D:/opt/files/event/28', 'tnsnames.ora');
res.download(paths,function(err, data) {
if(err) {
console.log('download faied');
res.sendStatus(404);
}
})
}