asp.net webapi 2 post parameter is always null

Question

I have been trying to figure this our for the last hour, but I can't see what's wrong with it

the post is from a xamarin app that I'm writing, using restsharp portable client

POST http://192.168.30.103:8080/api/Order HTTP/1.1
Authorization: Basic xxxx
Content-Length: 51
Content-Type: application/json; charset=utf-8
Host: 192.168.30.103:8080
Connection: Keep-Alive
Pragma: no-cache

{"CheckinCount":1,"EventId":16630,"OrderNo":470292}

It hits the server Post API correctly, but the parameter is always null

 public IHttpActionResult Post([FromBody]string source) {
        dynamic data = JsonConvert.DeserializeObject(source);
        int checkInCount = data.CheckinCount;
        int eventId = data.EventId;
        int orderNo = data.OrderNo;
        return Ok();
    }

I can't figure out why...

Why do you do the deserialization manually and not leave it to web api? — Jürgen Röhr, Dec 02 '16 at 07:39
`{"CheckinCount":1,"EventId":16630,"OrderNo":470292}` isn't a string. It's an object instead. — Amit Kumar Ghosh, Dec 02 '16 at 07:44
I didn't want to add another DTO for a last minute API addon, but I'll give it a whirl — Danish, Dec 05 '16 at 00:31

score 3 · Accepted Answer · answered Dec 02 '16 at 07:41

3

Do you always send the same parameters? If so, could you create a static object instead of using a dynamic one? Something like an EventRequest that you pass in instead?

public class EventRequest
{
    public int CheckinCount { get; set; }
    public int EventId { get; set; }
    public int OrderNo { get; set; }
}

Your Post action then becomes:

public IHttpActionResult Post(EventRequest request) {
    // do something with request
    return Ok();
}

answered Dec 02 '16 at 07:41

levelnis

7,665
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thanks that worked, however i'd still be interested if I wanted to read raw json from body, how would I do it ? – Danish Dec 05 '16 at 00:38
1

Just for my own note, if you forget public on the properties, it won't give you an error, just an empty object with null values for properties. I promise to never ever copy and paste code again! – Zachary Scott Apr 12 '17 at 05:08

score 1 · Answer 2 · answered Apr 23 '21 at 11:15

1

For me, it was the value of that is being sent by checkbox. Checkbox was sending true but for JSON, value must be between quotations i.e. "true".

answered Apr 23 '21 at 11:15

krishna422

266
1
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score 0 · Answer 3 · edited May 23 '17 at 10:30

0

asp.net webapi 2 post parameter is always null

3 Answers3

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