Aspnetcore: [Blazor] StackOverflowException thrown on introduction of view model

Created on 19 Jul 2019 · 5Comments · Source: dotnet/aspnetcore

Following along the example provided in the docs here:
https://docs.microsoft.com/en-us/aspnet/core/blazor/forms-validation?view=aspnetcore-3.0 I am attempting to introduce a view model for the purposes of a dynamic form.

On navigation to the page that produces this error - the app crashes and the following is logged out:

Process is terminating due to StackOverflowException.

\TestManagementApp\bin\Debug\netcoreapp3.0\TestManagementApp.exe (process 16112) exited with code -1073741819.

The view model is quite simple (I hadnt fleshed anything out before I ran into this issue).

public class TestCaseRun
{
    public long Id { get; set; }

    public Dictionary<long, TestStepResult> Results { get; set; }
}

public class TestStepResult
{
    public string Actual { get; set; }
    public bool Passed { get; set; }
}

To reproduce this error all I had to do was initialise the object like in my razor component as done in the example provided:

@code
{
// this line here 
    private TestCaseRun _testCaseRun = new TestCaseRun();

    [Parameter]
    private long TestCaseId { get; set; }

    protected override async Task OnInitAsync()
    {
        _results = await DbContext.TestSteps
                                  .Where(x => x.TestCaseId == TestCaseId)
                                  .ToListAsync();
    }

    private List<TestStep> _results = new List<TestStep>();

    private void HandleValidSubmit()
    {
        Console.WriteLine("OnValidSubmit");
    }
}

I was able to identify this line as the cause by commenting it out and attempting to navigate back to my razor component and was succcessful.

Expected behavior
I navigate to the page as normal and successful load occurs.

Additional context

dotnet --info output

.NET Core SDK (reflecting any global.json):
 Version:   3.0.100-preview6-012264
 Commit:    be3f0c1a03

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.17134
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\3.0.100-preview6-012264\

Host (useful for support):
  Version: 3.0.0-preview6-27804-01
  Commit:  fdf81c6faf

.NET Core SDKs installed:
  2.1.0-preview1-007063 [C:\Program Files\dotnet\sdk]
  2.1.100 [C:\Program Files\dotnet\sdk]
  2.1.101 [C:\Program Files\dotnet\sdk]
  2.1.102 [C:\Program Files\dotnet\sdk]
  2.1.202 [C:\Program Files\dotnet\sdk]
  2.1.300-preview1-008174 [C:\Program Files\dotnet\sdk]
  2.1.300 [C:\Program Files\dotnet\sdk]
  2.1.400 [C:\Program Files\dotnet\sdk]
  2.1.500 [C:\Program Files\dotnet\sdk]
  2.1.502 [C:\Program Files\dotnet\sdk]
  2.1.503 [C:\Program Files\dotnet\sdk]
  2.1.504 [C:\Program Files\dotnet\sdk]
  2.1.505 [C:\Program Files\dotnet\sdk]
  2.1.601 [C:\Program Files\dotnet\sdk]
  2.1.602 [C:\Program Files\dotnet\sdk]
  2.1.700 [C:\Program Files\dotnet\sdk]
  2.1.701 [C:\Program Files\dotnet\sdk]
  2.1.800-preview-009696 [C:\Program Files\dotnet\sdk]
  2.2.104 [C:\Program Files\dotnet\sdk]
  3.0.100-preview6-012264 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
  Microsoft.AspNetCore.All 2.1.0-preview1-final [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.1.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.All 2.2.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.0-preview1-final [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.1.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 2.2.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.0.0-preview6.19307.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.0-dev-di-25621-02 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.0-preview1-26216-03 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.2.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

area-blazor question

Source

lachis

All 5 comments

Thank you for filing this issue. In order for us to investigate this issue, please provide a minimalistic repro project that illustrates the problem.

mkArtakMSFT on 19 Jul 2019

https://github.com/lachis/testmanagement/tree/master/TestManagementApp this is the repo it is occurring in. Hopefully it is as minimalistic as you require, it only has some extra EF core stuff in there but apart from that there is not much special about it,

See the TestCaseRun razor page for the page that is causing the app to crash when navigated to

lachis on 20 Jul 2019

Is this OK ?
You've got a component in your app named TestCaseRun.razor in whose code behind part you instantiate an object of the type TestManagementApp.ViewModels.TestCaseRun as follows:

private TestCaseRun _testCaseRun = new TestCaseRun();

I've noticed that you face difficulties in naming your objects and namespaces, such as DbContext namespace... Such naming can lead to subtle bugs that are likely to end your career...

Hope this helps...

enetstudio on 21 Jul 2019

😕2

You've got a component in your app named TestCaseRun.razor in whose code behind part you instantiate an object of the type TestManagementApp.ViewModels.TestCaseRun as follows:

Thanks for looking at this. It seems really like that this is the problem. You could cause a similar problem to this using regular C#.

@lachis does this made sense?

I've noticed that you face difficulties in naming your objects and namespaces, such as DbContext namespace... Such naming can lead to subtle bugs that are likely to end your career...

@enetstudio - I appreciate your help looking at this but please be nice. If you meant this as a joke, I don't think it comes across that way over the internet. It's easy to make a mistake like this and we don't want anyone to feel like they are being punished for asking for help.