POST request from Postman fails model validation

Question

Inside my ASP.NET WebApi program, I have an Author model:

public class Author
{
    public int Id { get; set; }
    [Required] public string Name { get; set; }
}

I also have an AuthorsController , with a PostAuthor(Author author) method:

// POST: api/Authors
[ResponseType(typeof(Author))]
public async Task<IHttpActionResult> PostAuthor(Author author)
{
    if (!ModelState.IsValid)
    {
        return BadRequest(ModelState);
    }

    // etc.
}

When I send a POST request programmatically inside my unit tests, HTTP Status Code 201 Created is returned:

However, when I send a POST request using Postman , I receive HTTP Status Code 400 Bad Request instead:

As you can see, when I send a POST request using Postman , the argument passed into the PostAuthor(Author author) method is null , and model validation fails as a result:

What should I do to ensure that POST requests from Postman can be processed?

Answer 1

Couple of changes: define it as HttpPost and use FromBody like

// POST: api/Authors
[HttpPost]
[ResponseType(typeof(Author))]
public async Task<IHttpActionResult> PostAuthor([FromBody] Author author)
{
    if (!ModelState.IsValid)
    {
        return BadRequest(ModelState);
    }

    // etc.
}

Answer 2

在邮递员正文中用=替换=，毕竟是JSON。

Answer 3

If you send in application/json and your API wait as INBOUND JSON, so try to send in JSON format, something like

{
"Id":"6",
"Name":"P.G. Wodehouse"
}