linq subquery child collection to string

Question

Hi All,

i am trying to figure out how to write a linq query that will return a child collections "name" property as a string.

I have a BO that has a "options" property where the options are the "name" property of each option in an "order" object.

I would like the result to look something like

order.id = 12312
order.date = 12/03/10
order.options = "Option 1 Name, Option 2 Name, Option 3 Name"

I hope this makes sense. thanks for any and all help!

Answer 1

While Aggregate will work it has O(n²) performance. If you need better performance you can use string.Join. Unfortunately this method doesn't accept an IEnumerable<string> so you have to also use ToArray to get what you want:

string.Join(", ", options.Select(o => o.Name).ToArray())

Answer 2

You can use Aggregate:

options.Aggregate((current, next) => current + ", " + next);

Note that this generates a new string for each operation, so if your options list is long you are better off using an old school approach with StringBuilder