C# Enumerable Sum(IEnumerable, Func)
Description
Computes the sum of the sequence of Double values that are obtained by invoking a transform function on each element of the input sequence.
Syntax
public static double Sum<TSource>(
this IEnumerable<TSource> source,
Func<TSource, double> selector
)
Parameters
TSource- The type of the elements of source.source- A sequence of values that are used to calculate a sum.selector- A transform function to apply to each element.
Returns
returns The sum of the projected values.
Example
using System;// w w w . j av a2 s. co m
using System.Linq;
using System.Collections.Generic;
public class MainClass{
public static void Main(String[] argv){
List<Package> packages =
new List<Package>
{ new Package { Company = "A", Weight = 25.2 },
new Package { Company = "B", Weight = 18.7 },
new Package { Company = "C", Weight = 61.0 },
new Package { Company = "D", Weight = 33.8 } };
double totalWeight = packages.Sum(pkg => pkg.Weight);
Console.WriteLine("The total weight of the packages is: {0}", totalWeight);
}
}
class Package{
public string Company { get; set; }
public double Weight { get; set; }
}
The code above generates the following result.
