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LastOrDefault: Where an Element Is Not Found

Posted on March 27, 2015June 27, 2015 by coder

using System; using System.Linq; using System.Collections; using System.Collections.Generic; public class Employee { public int id; public string firstName; public string lastName; public static ArrayList GetEmployeesArrayList() { ArrayList al = new ArrayList(); al.Add(new Employee { id = 1, firstName = "J", lastName = "R" }); al.Add(new Employee { id = 2, firstName = "W", lastName = "G" }); al.Add(new Employee { id = 3, firstName = "A", lastName = "H" }); al.Add(new Employee { id = 4, firstName = "D", lastName = "L" }); al.Add(new Employee { id = 101, firstName = "K", lastName = "F" }); return (al); } public static Employee[] GetEmployeesArray() { return ((Employee[])GetEmployeesArrayList().ToArray(typeof(Employee))); } } public class MainClass { public static void Main() { Employee emp = Employee.GetEmployeesArray().LastOrDefault(e => e.id == 5); Console.WriteLine(emp == null ? "NULL" : string.Format("{0} {1}", emp.firstName, emp.lastName)); } }

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using System; using System.Linq; using System.Collections; using System.Collections.Generic; public class Employee {     public int id;     public string firstName;     public string lastName;       public static ArrayList GetEmployeesArrayList() {         ArrayList al = new ArrayList();         al.Add(new Employee { id = 1, firstName = "J", lastName = "R" });         al.Add(new Employee { id = 2, firstName = "W", lastName = "G" });         al.Add(new Employee { id = 3, firstName = "A", lastName = "H" });         al.Add(new Employee { id = 4, firstName = "D", lastName = "L" });         al.Add(new Employee { id = 101, firstName = "K", lastName = "F" });         return (al);     }       public static Employee[] GetEmployeesArray() {         return ((Employee[])GetEmployeesArrayList().ToArray(typeof(Employee)));     } } public class MainClass {     public static void Main() {         Employee emp = Employee.GetEmployeesArray().LastOrDefault(e => e.id == 5);           Console.WriteLine(emp == null ? "NULL" :           string.Format("{0} {1}", emp.firstName, emp.lastName));     } }

uses Skip to get all but the first 4 elements of the array.

Posted on February 27, 2015June 27, 2015 by coder

using System; using System.Collections.Generic; using System.Linq; using System.Text; public class MainClass{ public static void Main() { int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7}; var allButFirst4Numbers = numbers.Skip(4); Console.WriteLine("All but first 4 numbers:"); foreach (var n in allButFirst4Numbers) { Console.WriteLine(n); } } }

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using System; using System.Collections.Generic; using System.Linq; using System.Text;   public class MainClass{ public static void Main() {               int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7};                          var allButFirst4Numbers = numbers.Skip(4);                          Console.WriteLine("All but first 4 numbers:");             foreach (var n in allButFirst4Numbers) {                 Console.WriteLine(n);             }         } }