CODEWITHSUNDEEP
entity-frameworkasp.net-web-apiodata
user487351
user487351

Reputation: 61

.net WebApi IQueryable EF

I'm using .net web Api with Entity Framework. Its really nice that you can just do

[EnableQuery]
public IQueryable<Dtos.MyDto> Get()
{
  return dbContext.MyEntity.Select(m => new MyDto 
  {
     Name = m.Name
  });
}

And you get odata applying to the Iqueryable, note also returning a projected dto.

But that select is a expression and so its being turned to into sql. Now in the above case that's fine. But what if I need to do some "complex" formatting on the return dto, its going to start having issues as SQL wont be able to do it.

Is it possible to create an IQueryable Wrapper? 

QWrapper<TEntity,TDo>(dbcontext.MyEntity, Func<TEntity,TDo> dtoCreator)

it implements IQueryable so we still return it allowing webapi to apply any odata but the Func gets called once EF completes thus allowing 'any' .net code to be called as its not converting to SQL.

I don't want to do dbContext.MyEntity.ToList().Select(...).ToQueryable() or whatever as that will always return the entire table from the db.

Thoughts?

Upvotes: 0

Views: 416

Answers (1)

challenh
challenh

Reputation: 86

since you query already returns the data you expected, how about adding .Select(s=>new MyEntity(){ Name=s.Name }) for returning them as OData response? like: 

   return dbContext.MyEntity.Select(m => new MyDto 
   {
      Name = m.Name
   }).Select(s=>new MyEntity(){ Name=s.Name });

Upvotes: 0

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