How to use list.Sum<> in System.Collections.Generic

List.Sum<>

This will return the summation of named attribute.

List<Item> listItem = new List<Item>();

Item T1 = new Item() { Name = "A", Amount = 100 };

Item T2 = new Item() { Name = "B", Amount = 600 };

Item T3 = new Item() { Name = "C", Amount = 100 };

Item T4 = new Item() { Name = "D", Amount = 150 };

Item T5 = new Item() { Name = "E", Amount = 200 };

listItem.Add(T1);

listItem.Add(T2);

listItem.Add(T3);

listItem.Add(T4);

listItem.Add(T5);

Decimal D = listItem.Sum(P=>P.Amount);

// sum of Amount

Conditional Sum

Assume that you want to get the summation of Amount lager than 100

Decimal D = listItem.Where(P=>P.Amount>100).Sum(P=>P.Amount);

List.Sum()

This will return the summation of the list.

List<int> intList = new List<int>();

intList.Add(2);

intList.Add(3);

intList.Add(4);

int sum = intList.Sum();

// sum of Amount