Question

I have 3 .net Lists items, I need to merge them all into one, to order them and bind them to a datagrid. However, I need a way of indicating which original list each item came from, so that I can identify this in the datagrid (change color or font etc).

Can anyone suggest the best way to do this?

Answer 1

List<Foo> list1 = new List<Foo>();
List<Foo> list2 = new List<Foo>();
List<Foo> list3 = new List<Foo>();

var query = list1.Select(foo => new { foo, list = "list1" })
    .Concat(list2.Select(foo => new { foo, list = "list2" }))
    .Concat(list3.Select(foo => new { foo, list = "list3" }))
    .OrderBy(item => item.foo); // whatever you need to order by 

Expand the properties as needed.