Question

Actually haven’t found the answer for this one.

What for and why do i need a complex type in ef4?

Please give a code example in c# it will be more than appreciated.

Thank you very much in advance.

Answer 1

Some information might be better suited to fit into a complex type. For example given that you have a product type, which contains some information about it’s width, height and depth. You could create a property/column for each one of them. Or just create a single property using a complex-type which is mapped to multiple columns:

public class Dimensions
{
    public double Width { get; set; }
    public double Height { get; set; }
    public double Depth { get; set; }
}

public class Product
{
    public Dimensions Dimensions { get; set; }
}

Your ´Products´ table might actually look like this: Id, Name, Width, Height, Depth; but you get a much nicer object.

Also complex-types can be used to solve some problems with the EF and custom user types. But I won’t get into that now.