NodeJS Ajax请求

js代码

function show(fileId){

    $.ajax({
        url:'http://localhost:80/show',
        dataType:'jsonp',
        data:{
            'fileId':fileId
        },
        cache:false,
        jsonp:'callback',
        timeout:5000,
        success: function (data) {
            var data = $.parseJSON(data);
            alert(data.message);
        },
        error: function(jqXHR, textStatus, errorThrown) {
            alert('error ' + textStatus + " " + errorThrown);
        }
    });
}

NodeJS 后台代码

var express = require('express');
var logger = require('../common/logger');
var url = require('url');

exports.show = function (req, res, next) {
    var queryObj = url.parse(req.url,true).query;
    res.send(queryObj.callback+'(\'{"message": "展示ID为' +queryObj.fileId+
    '的信息"}\')');
}