Change order in List<Rebar> rebars

[dawid.deptula]

Do you know how to order rebars in list by Bar Length parameter. I try sth like this:

 rebars = rebars.OrderBy(rebar => rebar.LookupParameter("Bar Length").AsDouble()) as List<Rebar>;

but it doesn't work. I have rebars count = 0.

[sahin.ikbal · Accepted solution]

Are there rebars in the first place before ordering?
Instead of 

 rebars = rebars.OrderBy(rebar => rebar.LookupParameter("Bar Length").AsDouble()) as List<Rebar>;

try with

rebars = rebars.OrderBy(rebar => rebar.LookupParameter("Bar Length").AsDouble()).ToList();