Difference[Answered] RSS

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  jagjit saini

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  Difference

  Feb 17, 2021 02:16 PM|jagjit saini|LINK

  Hi

    What is the difference between Virtual & List in below lines. I am using Ado.Net Entity Model

  public virtual ICollection<Employee> Employees { get; set; }
          public List<Employee> Employees { get; set; } 

  Thanks

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  mgebhard

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  Re: Difference

  Feb 17, 2021 02:53 PM|mgebhard|LINK

  jagjit saini

  What is the difference between Virtual & List in below lines. I am using Ado.Net Entity Model

  public virtual ICollection<Employee> Employees { get; set; }
          public List<Employee> Employees { get; set; } 

  The virtual keyword is identifies base members that can be overridden by a derived type.  See the the C# language reference to learn about the "virtual" keyword.

  https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/virtual

  And see the C# programming guide to learn inheritance fundamentals.

  https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/polymorphism

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  PaulTheSmith

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  Re: Difference

  Feb 17, 2021 10:40 PM|PaulTheSmith|LINK

  jagjit saini

  difference between Virtual & List

  They have nothing to do with each other.  'virtual' is a c# keyword and 'List' is the name of a class in the .Net Framework.

  Do you have a problem? What result are you trying to achieve?

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  SurferOnWww

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  Re: Difference

  Feb 18, 2021 12:40 AM|SurferOnWww|LINK

  jagjit saini

    What is the difference between Virtual & List in below lines. I am using Ado.Net Entity Model

  public virtual ICollection<Employee> Employees { get; set; }
          public List<Employee> Employees { get; set; } 

  “Virtual and List” is not a matter to discuss about difference.

  I understand that the above code define an entity class of Entity Framework. As for the “virtual” read the following document:

  Why Navigation Properties are virtual by default in EF

  As for the “List” see below:

  List<T> Class

• • Reply
  Jerry Cai

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  Re: Difference

  Feb 18, 2021 07:56 AM|Jerry Cai|LINK

  Hi,jagjit saini

  If you do not apply other functions, the 'virtual ICollection will be lazy-loaded. Lazy-loading will make related objects (child objects) are not

  loaded automatically with its parent object until they are requested. The List without the virtual, it uses eager loading while with virtual, it can

  use both. You can check the difference:

  Lazy loading:

  MyModel model = dbContext.MyModel.FirstOrDefault(a => a.Id == id);  // the Employees will not be loaded
  EMP e=model.Employees; //Employees loaded

  Eager loading :

  var model= await dbContext.MyModel          //whole MyModel will be loaded
                  .Include(s => s.currency) 
                  .ToList();

  Best Regards,

  Jerry Cai

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