C# 0 The Complete Reference

IEnumerable

, where 

T

 specifies the 

type of data being enumerated. The rest of the chapter assumes that a data source implements 

IEnumerable

. This interface is declared in 

System.Collections.Generic

. A class that 

implements

IEnumerable

 supports enumeration, which means that its contents can be 

obtained one at a time, in sequence. All C# arrays support 

IEnumerable

. Thus, arrays 

can be used to demonstrate the central concepts of LINQ. Understand, however, that LINQ 

is not limited to arrays.

A Simple Query

At this point, it will be helpful to work through a simple LINQ example. The following 

program uses a query to obtain the positive values contained in an array of integers:

// Create a simple LINQ query.

using System;

using System.Linq;

class SimpQuery {

  static void Main() {

    int[] nums =  { 1, -2, 3, 0, -4, 5 };

www.freepdf-books.com

---