Swashbuckle.AspNetCore.JsonMultipartFormDataSupport

Adds support for json in multipart/form-data requests.

Usage

1. Simple add this to your ConfigureServices

services.AddJsonMultipartFormDataSupport(JsonSerializerChoice.Newtonsoft);

Or manually:

• Binder

services
    .AddMvc(
        properties => {
            // ...
            properties.ModelBinderProviders.Insert(0, new FormDataJsonBinderProvider()); // Here
        }
    )

• Operation filter

services.AddSwaggerGen(c => {
        c.OperationFilter<MultiPartJsonOperationFilter>();
    });

2. Add to your Controller

[HttpPost]
[Consumes("multipart/form-data")] 
public async Task<IActionResult> Post([FromForm] MultipartFormData<Product> multiPartData) {
    var file = multiPartData.File;
    var product = multiPartData.Json;
}

or

[HttpPost]
[Consumes("multipart/form-data")] 
public async Task<IActionResult> Post([FromForm] MultipartRequiredFormData<Product> multiPartData) {
    var file = multiPartData.File;
    var product = multiPartData.Json;
}

Or you can create your on wrapper

public class MyWrapper {
    [FromJson] // <-- This attribute is required for binding.
    public MyModel Json { get; set; }

    public IFormFile File { get; set; }
}

and then

[HttpPost]
[Consumes("multipart/form-data")] 
public async Task<IActionResult> Post([FromForm] MyWrapper myWrapper) {
    // code
}

Notes:

It automatically adds examples from class which implements IExampleProvider<MyModel>.