Create a list from another list

Question

Let's say I have:

class Plus5 {
    Plus5(int i) {
         i+5;
     }
}
List<int> initialList = [0,1,2,3]

How I can create, from initialList, another list calling Plus5() constructor for each element of initialList.

Is here something better than the following?

List<Plus5> newList = new List<Plus5>();
initialList.ForEach( i => newList.Add(Plus5(int)));

Answer 1

How i can create, from initialList, another list calling Plus5() constructor for each element of initialList?

So the result is List<Plus5> newList and you want to create a new Plus5 for every int in initialList:

List<Plus5> newList = initialList.Select(i => new Plus5(i)).ToList();

If you want to micro-optimize(save memory):

List<Plus5> newList = new List<Plus5>(initialList.Count);
newList.AddRange(initialList.Select(i => new Plus5(i)));

Answer 2

Use LINQ to add 5 to each number in your list.

var result = initialList.Select(x => x + 5);