Controller action with multiple parameters

Question

I am trying to understand what I think is a model binding problem in my ASP.NET Core project. I have the following 'Index' controller action:

[HttpGet]
public async Task<IActionResult> Index(SortFilterIndexOptions options) { ... }

The SortFilterIndexOptions are four members defined in the following class:

public class SortFilterIndexOptions
{
    public int SelectedBirdId { get; set; }
    public bool ShowAll { get; set; }
    public bool ShowInTable { get; set; }
    public int page { get; set; }
}

These enable the user to filter a paged index page. The bool members are linked to checkbox controls.

I have a fault if the 'ShowAll' bool member is changed to TRUE and then try to navigate to a different page. As the screenshot, below, shows the 'ShowAll' parameter part of the url then contains two bool values ('ShowAll=true, false'):

which of course results in a parse error ('FormatException: String was not recognized as a valid Boolean').

What's happening here? It only happens when the 'ShowAll' parameter is toggled to TRUE. Is it a routing problem because it does not follow the default route pattern? Or is it a problem with the ModelBinder? I am just trying to understand what is going on so I can take the right action. Any help would be appreciated...

Update

This is now issue #3246 ('ModelBinding error with boolean values') on the asp/Home GitHub repository (originally raised by me as issue #1711 on the dotnet/Core repository).

The error message is pretty clear...ShowAll=true,false is not valid as a boolean. Should work with just ShowAll=true — Nkosi
– Nkosi, Commented May 16, 2018 at 10:34
Yes, I am trying to work out why it adding the two Boolean values. When I click the next page button. This happens the ShowAll is toggled to true. Why is it appending the second ‘false’ value in the url? — Winthorpe
– Winthorpe, Commented May 16, 2018 at 10:43
@CodeCaster. It is a Bootstrap Toggle control. So the same as a checkbox. In a form to a GET — Winthorpe
– Winthorpe, Commented May 16, 2018 at 10:44

Nkosi · Accepted Answer · 2018-05-16 10:45:37Z

2

The error message is pretty clear...ShowAll=true,false is not valid as a Boolean.

The model binder is receiving the following string "true,false" from the query string for that parameter and would then try to parse that as a Boolean, which would fail as you have already seen.

Similar to trying

bool value = bool.Parse("true,false");

Should work with just ShowAll=true

edited May 16, 2018 at 10:45

answered May 16, 2018 at 10:38

Nkosi

249k38 gold badges472 silver badges506 bronze badges

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

5 Comments

CodeCaster Over a year ago

"When the checkbox is checked, the ModelBinder will automatically take care of extracting the 'true' from the 'true,false'"

Nkosi Over a year ago

@CodeCaster I am wondering now if the model binder in core has that capability?

CodeCaster Over a year ago

Well I know core likes to break a lot of things, but something as fundamental as a checkbox on a form...?

Winthorpe Over a year ago

Yes it seems odd. I will change to a drop down list of enumerated values and see if it works. To try to see if the fault is isolated to the checkbox... As I mentioned, one can navigate the different pages of the checkboxes are left as false. It breaks when one is switched to true...

Winthorpe Over a year ago

I replaced the checkboxes with drop down lists and the model binding issue was resolved. Which suggests the issue was caused by the ModelBinder with checkboxes. I will leave the question open for a bit to see if anyone can add anything...

Winthorpe · Accepted Answer · 2018-07-13 13:58:46Z

0

This issue was investigated by the aspnet/Mvc team under issue #8043.

There is no problem with the ModelBinder. The problem was caused by my pager code, which constructs the url. Please use the link to view the full conversation which contains a detailed explanation from the aspnet/Mvc team and sample code provided by me.

answered Jul 13, 2018 at 13:58

Winthorpe

1,2724 gold badges22 silver badges43 bronze badges

Collectives™ on Stack Overflow

Controller action with multiple parameters

2 Answers 2

5 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

5 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related