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I'm having difficulty identifying where in a ASP.NET Core app we specify that a model can have the FirstOrDefaultAsync method enabled. I've previously scaffolded two models to razor pages, and for those I can write async method like so:

component = await Context.component.FirstOrDefaultAsync(m => m.ID == id);

However, for this new model that I scaffolded, I used a view Model but when I swapped the models, I get an error when I use the FirstOrDefaultAsync method.

'DbSet' does not contain a definition for 'FirstOrDefaultAsync' and no accessible extension method 'FirstOrDefaultAsync' accepting a first argument of type 'DbSet' could be found (are you missing a using directive or an assembly reference?)

I've made sure that the necessary namespaces have been included in the file, and the DBContext file includes the model

public DbSet<update> update { get; set; }

I made sure to run dotnet restore and restart VSCode and am unable to find answers searching online or in the documentation

Stanislav Dontsov
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Roshan Manuel
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  • you didnt show code of how you try to invoke firstordefaultasync and it gives you error – nbokmans Mar 10 '20 at 12:49
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    You can use that extension method anywhere as long as you are referencing the `EntityFramework.dll` and have the line `using System.Data.Entity;` – DavidG Mar 10 '20 at 12:54

1 Answers1

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I thought I made sure I had all the include statements I needed, but somehow using Microsoft.EntityFrameworkCore; got deleted. Re-adding it resolved the issue.

Roshan Manuel
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