how to filter and sum using linq

Question

what is the best LINQ approach for with no performance loss? how could we do the same thing using LINQ iterating the list only once?

class Employee  
{  
            


        

Answer 1

Try this for getting the total income

var totalIncomeOfToList = myList.Where(e => e.empType == 1).Sum(e => e.income);

If you also want the list of filtered employees then:

var toList = myList.Where(e => e.empType == 1).ToList();
var totalIncomeOfToList = toList.Sum(e => e.income);

The performance will be slightly better with a foreach, but this way the code will be much clear and precise.