javascript - frombody How to pass json POST data to Web API method as an object?

4 Answers

Working with POST in webapi can be tricky! Would like to add to the already correct answer..

Will focus specifically on POST as dealing with GET is trivial. I don't think many would be searching around for resolving an issue with GET with webapis. Anyways..

If your question is - In MVC Web Api, how to- - Use custom action method names other than the generic HTTP verbs? - Perform multiple posts? - Post multiple simple types? - Post complex types via jQuery?

Then the following solutions may help:

First, to use Custom Action Methods in Web API, add a web api route as:

public static void Register(HttpConfiguration config)
        name: "ActionApi",
        routeTemplate: "api/{controller}/{action}");

And then you may create action methods like:

public string TestMethod([FromBody]string value)
    return "Hello from http post web api controller: " + value;

Now, fire the following jQuery from your browser console

    type: 'POST',
    url: 'http://localhost:33649/api/TestApi/TestMethod',
    data: {'':'hello'},
    contentType: 'application/x-www-form-urlencoded',
    dataType: 'json',
    success: function(data){ console.log(data) }

Second, to perform multiple posts, It is simple, create multiple action methods and decorate with the [HttpPost] attrib. Use the [ActionName("MyAction")] to assign custom names, etc. Will come to jQuery in the fourth point below

Third, First of all, posting multiple SIMPLE types in a single action is not possible. Moreover, there is a special format to post even a single simple type (apart from passing the parameter in the query string or REST style). This was the point that had me banging my head with Rest Clients (like Fiddler and Chrome's Advanced REST client extension) and hunting around the web for almost 5 hours when eventually, the following URL proved to be of help. Will quote the relevant content for the link might turn dead!

Content-Type: application/x-www-form-urlencoded
in the request header and add a = before the JSON statement:
={"Name":"Turbo Tina","Email":"na@Turbo.Tina"}

PS: Noticed the peculiar syntax?

Anyways, let us get over that story. Moving on:

Fourth, posting complex types via jQuery, ofcourse, $.ajax() is going to promptly come in the role:

Let us say the action method accepts a Person object which has an id and a name. So, from javascript:

var person = { PersonId:1, Name:"James" }
    type: 'POST',
    url: 'http://mydomain/api/TestApi/TestMethod',
    data: JSON.stringify(person),
    contentType: 'application/json; charset=utf-8',
    dataType: 'json',
    success: function(data){ console.log(data) }

And the action will look like:

public string TestMethod(Person person)
    return "Hello from http post web api controller: " + person.Name;

All of the above, worked for me!! Cheers!

web api post json string

ASP.NET MVC4 Web API application defines post method to save customer. Customer is passed in json format in POST request body. Customer parameter in post method contains null values for properties.

How to fix this so that posted data will passed as customer object ?

If possible Content-Type: application/x-www-form-urlencoded should used since I dont know how to change it in javascript method which posts form.


public class CustomersController : ApiController {

  public object Post([FromBody] Customer customer)
            return Request.CreateResponse(HttpStatusCode.OK,
                customer = customer

public class Customer
        public string company_name { get; set; }
        public string contact_name { get; set; }


POST http://localhost:52216/api/customers HTTP/1.1
Accept: application/json, text/javascript, */*; q=0.01
X-Requested-With: XMLHttpRequest
Content-Type: application/x-www-form-urlencoded; charset=UTF-8


Use the JSON.stringify() to get the string in JSON format, ensure that while making the AJAX call you pass below mentioned attributes:

  • contentType: 'application/json'
  • dataType: 'json'

Below is the give jquery code to make ajax post call to web api:

var product =
        productGroup: "Fablet",
        productId: 1,
        productName: "Lumia 1525 64 GB",
        sellingPrice: 700

    URL: 'http://localhost/api/Products',
    type: 'POST',
    contentType: 'application/json',
    dataType: 'json',
    data: product,
    success: function (data, status, xhr) {
    error: function (xhr, status, error) {
        alert('Update Error occurred - ' + error);

Following code to return data in the json format ,instead of the xml -Web API 2 :-

Put following line in the Global.asax file

GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;