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How can I return a list of strings from a LINQ to Entities many-many relationship?

开发者 https://www.devze.com 2022-12-21 07:45 出处:网络
I have a view model that needs to encapsulate a couple of many-to-many relationships. I have my LINQ to Entites query that returns the appropriate list, but can\'t figure out how to return a list of

I have a view model that needs to encapsulate a couple of many-to-many relationships.

I have my LINQ to Entites query that returns the appropriate list, but can't figure out how to return a list of objects.

I have a Foo table, and a Bar table. Bar has a FK to Foo.ID, and a Description string. I want to create a FooViewModel that has Foo.ID, as well as list of all the Bar.Descriptions.

  public class FooViewModel {
    public int ID {get; set; }
    public IEnumerable Descriptions { get; set; }
  }


  var all = from f in ctx.Foo.Include("Bar")
            select new FooViewModel
            {
              ID = f.ID,
              Descriptions = <insert magic here>
            };

W开发者_如何学Gohat am I missing?


In Linq to Sql, Foo objects would have a property "Bar" (or "Bars" if it's one-to-many), so it would be just:

var all = from f in ctx.Foo
            select new FooViewModel 
            { 
              ID = f.ID, 
              Descriptions = f.Bars;
            }; 

I'm told it works the same way in Linq-to-Entity, with the proviso that while that property is automatically create in L2S, there's some explicit task you must do manually to have L2e create it.

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