passing another class (files) value from view to controller directly from ViewModel

Question

FunwarsVM.cs

public class FunwarsVM : IFunwars
{
    public int Id { get; set; }
    public string Date { get; set; }
    public string OurTeam { get; set; }
    public string Status { get; set; }
    public string Opponent { get; set; }
    public string Score { get; set; }
    public int FileID { get; set; }

    public List<Funwars> Funwars { get; set; }

    [NotMapped]
    public  ImageUpload Files { get; set; }

    public FunwarsVM()  
    {
        this.Funwars = new List<Funwars>();
        this.Files = new ImageUpload();
    }
}

ImageUpload.cs

public class ImageUpload
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string MimeType { get; set; }
    public string FilePath { get; set; }


    [NotMapped]
    public List<IFormFile> Images { get; set; }
}

View (only image upload part)

<form id="holder" method="post" action="/Funwars/Add" enctype="multipart/form-data">

    <div class="form-group">

        <h3>Screenshots</h3>

        <input type="file" name="files.images" value="@Model.Files.Images" multiple />

    </div>       
    <input type="submit" name="submit" value="Submit" />
</form>

Controller

[HttpPost]
public async Task<IActionResult> Add(FunwarsVM model)
{

    model.Add();
    return RedirectToAction("Index",model);
}

So guys, I want to pass Image files from view to controller. When I am passing @Model.Files.Images in my view, it means I am passing List<IFormFile> to my model, but it passes null!

but when I add

public List<IFormFile> Images { get; set;}

directly to my FunwarsVM, and then pass @Model.Images to my View, it returns right pictures I am adding!

why won't it work when I am calling that List<IFormFile> object from my View by after I create instance of ImageUpload model, but when i am calling directly it works!?

Did you ensure you are setting the form attribute enctype="multipart/form-data"? https://stackoverflow.com/questions/4526273/what-does-enctype-multipart-form-data-mean — Canica, Feb 13 '19 at 13:58
Can you post your controller code? Your auto binding might not be defined correctly. — bdparrish, Feb 13 '19 at 14:06

bdparrish · Answer 1 · 2019-02-13T14:35:53.103

0

Because your controller action only has the FunwarsVM model in the parameters, then it will never be binded correctly unless it is part of FunwarsVM object, which is why it works when you utilize the model.

if you add a new parameter List<IFormFile> images, then it should work as expected. Don't quote me on the way to define the parameter, but I believe it needs to have the same name as the name attribute to get automatically binded.

EDIT

Add the second parameter so that there is something to bind it to.

[HttpPost]
public async Task<IActionResult> Add(FunwarsVM model, List<IFormFile> images)
{
    model.Add();
    return RedirectToAction("Index",model);
}

edited Feb 13 '19 at 14:35

answered Feb 13 '19 at 14:14

bdparrish

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Sir, i also fixed that name attribute and tried on that way but it doesn't affect, well, thank you for information, but unfortunately it didn't solve my problem. – Artur_Kamalyan Feb 13 '19 at 14:19
did you add the second parameter to your Action? – bdparrish Feb 13 '19 at 14:22
so,as i got, i can't pass that value only within my FunwarsVM? – Artur_Kamalyan Feb 13 '19 at 14:24
yes i know what you meant sir, but i am looking for answers about passing those values using only one model – Artur_Kamalyan Feb 13 '19 at 14:37
Just create a new class as the viewmodel, but you said you didn't want to use a view model – bdparrish Feb 13 '19 at 15:28

score 0 · Accepted Answer · answered Feb 13 '19 at 16:47

For some unknown reason ASP.NET Core doesn't bind file to a nested object if you pass only one property for it (Images in your case). So the solution is just add any other property of that class to view

<input type="hidden" name="files.id" />
<input type="file" name="files.images" value="@Model.Files.Images" multiple />

passing another class (files) value from view to controller directly from ViewModel

2 Answers2

EDIT