Question

I have an existing class Image which is used extensively throughout my application.
I need to return a generic list of images (List) to the frontend but as there is no stored proc in the 3ed party DB I am quering I need to use Linq to Sql.

I have create a dbtm file of the database I am quering in my DAL which looks like:

ImageCat
    ImageId
    Name
    Width
    DateModified
    Height
    CatId

My Image class is as follows

public class Image
{
 public int Id { get; set; }
 public string Name { get; set; }
 public int Width { get; set; }
 public int Height { get; set; }
}

My Linq to Sql is as follows:

var imageList = (from ic in db.ImageCats
   where ic.CatID.Contains(category)
 select ic).ToList();

var finalImageList = new List<Image>();
foreach (ImageCat ic in imageList)
{
 Image image = new Image();
 image.Id= ic.ImageID;
 image.Height = (int)ic.Height;
 image.Name = ic.Name;
 image.Width = (int)ic.Width;

 finalImageList.Add(image);   
}

I dont want to be looping through the linq to Sql result to setup my List. Is there an easier way. What is best practice? I dont like the idea of exposing my dbml classes to the presentation layer.

Answer 1

You can select directly to you Image class in the LINQ query

var imageList = (
    from ic in db.ImageCats
    where ic.CatID.Contains(category)
    select new Image()
    {
         Id= ic.ImageID,
         Height = (int)ic.Height,
         Name = ic.Name,
         Width = (int)ic.Width,
    }
).ToList();