c# modifying structs in a List

Question

Short question: How can I modify individual items in a List? (or more precisely, members of a struct stored in a List?)

Full e

Answer 1

If subItems was changed to a concrete List instead of the interface IList, then you'd be able to use the Sort method.

public List subItems;

So your whole loop becomes:

foreach (slotInfo sInf in gAllCats[c].items)
    sInf.subItems.Sort();

This won't require the contents of the struct to be modified at all (generally a good thing). The struct's members will still point to exactly the same objects.

Also, there are very few good reasons to use struct in C#. The GC is very, very good, and you'd be better off with class until you've demonstrated a memory allocation bottleneck in a profiler.

Even more succinctly, if items in gAllCats[c].items is also a List, you can write:

gAllCats[c].items.ForEach(i => i.subItems.Sort());

Edit: you give up too easily! :)

Sort is very easy to customise. For example:

var simpsons = new[]
               {
                   new {Name = "Homer", Age = 37},
                   new {Name = "Bart", Age = 10},
                   new {Name = "Marge", Age = 36},
                   new {Name = "Grandpa", Age = int.MaxValue},
                   new {Name = "Lisa", Age = 8}
               }
               .ToList();

simpsons.Sort((a, b) => a.Age - b.Age);

That sorts from youngest to oldest. (Isn't the type inference good in C# 3?)