jQuery POST到Node.JS失败

Question

I'm trying to expand my horizons by getting familiar with node.js (I'm a .NET developer by profession), and I'm having trouble with what I assumed would be a simple POST example. I do have experience with jQuery, so node.js is the one relative unknown for me in this sample website I'm building.

The node.JS server code:

var express = require('express');
var app = express();

app.configure(function() {
    app.use(express.bodyParser());
    app.use(app.router);
    app.use(express.logger());
});

app.use(express.static(__dirname + '/public/PRB_Presentation'));

app.post('/GetPage', function(request, response){
    console.log(request.body.pageNumber);
    response.send(request.body.pageNumber);
});

var port = 80;
app.listen(port);
console.log('Listening on port: ' + port);

My client-side jQuery logic:

function getPage(pageNumber){
        $.ajax({
            url: '/GetPage',
            type: 'POST',
            contentType: 'application/json; charset=utf-8',
            dataType: 'json',
            data: JSON.stringify({ pageNumber: pageNumber })
        }).done(function(data, textStatus, jqXHR) {
            console.log("Success: " + data);
        }).fail(function(jqXHR, textStatus, errorThrown) {
            console.log("Error: " + errorThrown);
        }).always(function() {
            console.log("Done!");
        })
        ;
    };

With my node.js server running, I do see the page number I send getting output to the console window correctly, but this is what I'm getting client-side:

Error: unknown
Done!

I assume I am doing something incredibly simple wrong here, but I can't quite figure it out.

EDIT

• request.body.pageNumber contains a single numeric digit (for example, 2)
• textStatus in fail() is simply "error"

Answer 1

The reason you're getting an error is because you're supplying a number in res.send() . Doing so sends the value as the HTTP status code, rather than the response body.

res.send(200);   -> HTTP 200 OK
res.send('200'); -> 200

The send() method accepts two arguments. If you supply one and it's a numerical value, then it will be interpreted as the HTTP status code to send. What you might find more applicable to what you're trying to do is res.json() .

app.post('/path', function(req, res) {
  res.json(request.body.page);
});

Otherwise, force the number to be sent as a string:

app.post('/path', function(req, res) {
  res.send('' + request.body.page);
});