Summarize list by property

Question

I have a list of objects like this:

List list = new List();
list.Add(new ClassName()
{
    Name = 1,
    Amount = 5
});
list.Ad         


        

Answer 1

var result = list.GroupBy(x => x.Name).Select(x => new MyClass() {Name=x.Key, Amount= x.Sum(y => y.Amount));

OR

List result = list.GroupBy(x => x.Name).Select(x => new MyClass() {Name=x.Key, Amount= x.Sum(y => y.Amount)).ToList();