Model binding not working for nested object

Question

I am trying to bind data in my model posted from postman in my below model:

public class VariantModel
{
    public int Id { get; set; }     
    public List<SubvariantModel> Subvariants { get; set; }
}

public class SubvariantModel
{
    public int Id { get; set; }
    public string Description { get; set; }
    public IFormFile Document { get; set; }
}

Every property is getting populated but only Document property is coming null as you can see here :

But surprisingly when i inspect http request object i see that file :

This is how i am posting data from POSTMAN :

Code :

[HttpPost]
public void Post([FromForm]VariantModel emp)
{
    var d = HttpContext.Request;
}

Can anybody tell me what could be the issue here?

Update :

Your key naming is very odd. The names should really be Subvariants[0].Document, not Subvariants[0][Document]. It's surprising that this actually works for Id and Description, but perhaps it simply doesn't for some reason with IFormFile. Seems odd, but I honestly don't see anything else wrong. — Chris Pratt
– Chris Pratt, Commented Apr 5, 2019 at 14:38
@ChrisPratt I tried like this Subvariants[0].Document as well but still getting null and yes indeed I am also not getting whats the problem here.Is this a bug in asp.net webapi core with model binder? — I Love Stackoverflow
– I Love Stackoverflow, Commented Apr 5, 2019 at 14:41
Not at all. This is very basic code, and I've run code virtually just like this. As long as the name in the post body follows the proper conventions for binding (which these seem to), then it will bind. — Chris Pratt
– Chris Pratt, Commented Apr 5, 2019 at 14:53
@ChrisPratt Then why this is not working right now.May be you have not taken IFormFile in your nested model.Is there any solution for this? — I Love Stackoverflow
– I Love Stackoverflow, Commented Apr 5, 2019 at 14:54
I just tested your code with ASP.NET Core 2.0 and everything worked fine for me. Could you please share your project on github and share the requests you performed via postman? — Oleksandr
– Oleksandr, Commented Apr 6, 2019 at 20:35

Graham Meehan · Accepted Answer · 2019-06-20 14:58:19Z

1

This is an issue I encountered as well. It is a known issue with nesting IFormFile as a View Model property in .NET Core v2.2.

The fix that worked for me is here.

answered Jun 20, 2019 at 14:58

Graham Meehan

4656 silver badges19 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Model binding not working for nested object

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related