Can't pass/receive values with POST request AJAX

Question

I'm trying to send some data with an Ajax Post request. The code of the request is the following:

$.ajax({
    url: "[url of page]",
    type: "POST",
    data: {saluto: true},
    dataType: 'text',
    success: function (response) {
        alert("successful" + response);
    },
    error: function () {
        alert("error");
    }
});

So in this case I should receive saluto = true

This is the Backend code:

[HttpPost("Test")]
public async Task<string> testHelloWorld(bool saluto)
{

    try
    {
        string testString = "Funziona";
        Console.Write(testString + ": " + saluto + "\n");
        return testString;
    }
    catch (Exception ex)
    {
        Log.Error("API(CallToXML) - Exception", ex);
        return null;
    }
}

So if saluto = true My console should print "Funziona: True" the OUTPUT tho is "Funziona: False"

If I try the same thing with a string, it won't print the string and just leaves the output like "Funziona: "

Why isn't my code reciving any data? Is there anything I'm doing wrong? Thanks.

Possible duplicate of [Bool parameter from jQuery Ajax received as literal string "false"/"true" in PHP](https://stackoverflow.com/questions/7408976/bool-parameter-from-jquery-ajax-received-as-literal-string-false-true-in-php) — peeebeee, Jul 17 '19 at 13:49
No but it does look like javascript, which is where the issue lies. — peeebeee, Jul 17 '19 at 13:51
@TommasoBertoni It's the same code, I just change the ```bool saluto``` to ```string saluto``` and the frontend request becames ```saluto:"prova"``` — Synapsis, Jul 17 '19 at 13:52
do you receive `saluto == false` when you send `true` from the frontend? — Tommaso Bertoni, Jul 17 '19 at 13:53
@TommasoBertoni Yes, I typed that at the end of the question — Synapsis, Jul 17 '19 at 13:54
@peeebeee If you read my js it is different from the one in your question so this is not the case. Anyway that didn t fix the problem. Thanks anyway for the help — Synapsis, Jul 17 '19 at 13:55
does it work if you send the request in `GET` instead of `POST`? — Tommaso Bertoni, Jul 17 '19 at 14:06
can you try to just send the value? using `data: true` or `data: "true"` — Tommaso Bertoni, Jul 17 '19 at 14:12
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/196580/discussion-between-tommaso-bertoni-and-synapsis). — Tommaso Bertoni, Jul 17 '19 at 14:26
I can't because I won't read that as the parameter my function asks for. The output will just be "Funziona: " leaving a blank space for the variable — Synapsis, Jul 17 '19 at 14:26

score 0 · Answer 1 · edited Jul 17 '19 at 15:30

0

Try removing "data: " and changing "url: " to: { value: "~/Controller/Method?saluto=true" }).

edited Jul 17 '19 at 15:30

Dmitriy Popov

2,150
3
25
34

answered Jul 17 '19 at 13:59

Julius Sabaliauskas

65
6

I tryed your method and it works but if I try to send a bigger string it won't work. The status of the request will still return an error – Synapsis Jul 17 '19 at 14:23

phuzi · Answer 2 · 2019-07-17T14:07:44.410

0

You'll need to change the signature of your action to

public async Task<string> testHelloWorld([FromBody]bool saluto)

By default the model binder looks for simple types in the request parameters not the body of the request.

Take a look Tadej's answer to Why do we have to specify FromBody and FromUri? for more information.

edited Jul 17 '19 at 14:07

answered Jul 17 '19 at 14:06

phuzi

12,078
3
26
50

2

The data is simple and sent using `POST`, therefore it can't be extracted `FromUri` – Tommaso Bertoni Jul 17 '19 at 14:07
@TommasoBertoni quite correct, should have been `[FromBody]` - corrected – phuzi Jul 17 '19 at 14:08
That's better, but I don't think that will fix it. asp.net should be able to understand the source if there is only one parameter or if the request comes by `POST` – Tommaso Bertoni Jul 17 '19 at 14:10
I'm currently checking if another answer works. I'll check this method in a sec, thanks – Synapsis Jul 17 '19 at 14:16
@phuzi Adding only the [FromBody] didn't help, it actually made it worse cause the request couldn't even be sent – Synapsis Jul 17 '19 at 14:22
@Synapsis with the `FromBody` did you get an http error response? – Tommaso Bertoni Jul 17 '19 at 14:32
Try setting `content: 'application/json'` on the request – phuzi Jul 17 '19 at 14:41
@Synapsis sounds like a different problem. Try adding `headers: { 'Content-Type': 'application/json;charset=utf-8' }` see here for info -> https://stackoverflow.com/questions/48988605/415-unsupported-media-type-jquery-ajax – phuzi Jul 17 '19 at 14:50
@phuzi still not working, I don't think that the data is the issue here – Synapsis Jul 18 '19 at 07:15

Can't pass/receive values with POST request AJAX

2 Answers2