Do you think this tutorial is wrong or outdated RSS

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  SaeedP

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  Do you think this tutorial is wrong or outdated

  Jan 15, 2021 08:54 PM|SaeedP|LINK

  Hello,

  I'm learning the Entity framework core and encountered in this tutorial:

  You can see the page here:

  https://entityframeworkcore.com/querying-data-basic-query

  And in there comes:

  Let's say we have a simple model which contains three entities.

  public class Customer
  {
      public int CustomerId { get; set; }
      public string FirstName { get; set; }
      public string LastName { get; set; }
      public string Address { get; set; }
      public virtual List<Invoice> Invoices { get; set; }
  }

  Load All data

  The following example loads all the data from Customers table.

  using (var context = new MyContext())
  {
      var customers = context.Customers.ToList();
  }

  This code isn't working. Is this wrong or outdated?

  thanks,

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  mgebhard

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  Re: Do you think this tutorial is wrong or outdated

  Jan 15, 2021 09:11 PM|mgebhard|LINK

  SaeedP

  This code isn't working. Is this wrong or outdated?

  The answer depends on what you mean by "isn't working".   

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  SaeedP

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  Re: Do you think this tutorial is wrong or outdated

  Jan 15, 2021 09:55 PM|SaeedP|LINK

  I mean this part:

  using (var context = new MyContext())
  {
      var customers = context.Customers.ToList();
  }
  
  

  Is correct? Visual studio doesn't accept it and appears red line under it!

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  mgebhard

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  Re: Do you think this tutorial is wrong or outdated

  Jan 16, 2021 02:05 AM|mgebhard|LINK

  SaeedP

  I mean this part:

  using (var context = new MyContext())
  {
      var customers = context.Customers.ToList();
  }
  
  

  Is correct? Visual studio doesn't accept it and appears red line under it!

  There is nothing technically wrong with the code.  The example assumes a fundamental understanding of EF Core.   

  I recommend the official documentation for learning EF Core.

  https://docs.microsoft.com/en-us/ef/core/get-started/overview/first-app?tabs=netcore-cli

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  Mikesdotnett...

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  Re: Do you think this tutorial is wrong or outdated

  Jan 16, 2021 09:13 AM|Mikesdotnetting|LINK

  SaeedP

  I mean this part:

  using (var context = new MyContext())
  {
      var customers = context.Customers.ToList();
  }
  
  

  Is correct? Visual studio doesn't accept it and appears red line under it!

  If you have red squiggles, I'm pretty certain that you have simply copied and pasted the code as-is and expected it to work. Have you actually created a DbContext called "MyContext" that has a DbSet called "Customers"? If not, the code will never work for you.

  That site is not a tutorial site. It's just a collection of snippets of code. You should go through a step-by-step tutorial for beginners like mgebhard suggested. You also need to review the basics of C#, I suggest.

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  SaeedP

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  Re: Do you think this tutorial is wrong or outdated

  Jan 17, 2021 05:15 PM|SaeedP|LINK

  But the site claims that was a tutorial nat snippet. Anyway, there is another site for the entity-framework core.

  I think that's from you, It is a cool site. I learned many things from that.

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  Mikesdotnett...

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  Re: Do you think this tutorial is wrong or outdated

  Jan 17, 2021 05:52 PM|Mikesdotnetting|LINK

  I have got one at learnentityframeworkcore.com. It has got a couple of step-by-step walkthroughs, but they probably need updating.

  https://www.learnentityframeworkcore.com/walkthroughs

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  PatriceSc

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  Re: Do you think this tutorial is wrong or outdated

  Jan 17, 2021 06:49 PM|PatriceSc|LINK

  Hi,

  It's close from code that works. For now it seems they don't show or shown earlier how to declare thre MyContext class My guess is that this class is not defined correctly (or at all?l). As pointed earlier it would be easier to guide you knowing which error message you have. We don't even know if this is a compile time or runtime error.

  Edit: see for example https://entityframeworkcore.com/approach-code-first if you need guidance about the MyContext class though it seems they switched at some point from Order/OrderDetail to Customer which perhaps doesn't help you to get something up and running.