使用C＃中的List从键值对中获取总和

Question

I have following code

var list = new List<KeyValuePair<string, int>>();

list.Add(new KeyValuePair<string, int>("Cat", 1));
list.Add(new KeyValuePair<string, int>("Cat", 2));
list.Add(new KeyValuePair<string, int>("Rabbit", 4));

Now I am trying to pass "Cat" and I should get sum of these keys in a variable.If I pass Rabbit, pass only that number

How to get this ? thinking of for-each....

Answer 1

Here is a Linq appraoch with Where() and Sum()

int result = list.Where(x => x.Key == "Cat").Sum(x => x.Value);

or

int result = list.Sum(x => x.Key == "Cat" ? x.Value : 0);