SingleOrDefault after where clause : SingleOrDefault « LINQ « C# / CSharp Tutorial






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().Where(e => e.id == 4).SingleOrDefault();
        Console.WriteLine(emp == null ? "NULL" :
          string.Format("{0} {1}", emp.firstName, emp.lastName));
    }
}








22.67.SingleOrDefault
22.67.1.Use SingleOrDefault
22.67.2.SingleOrDefault: Where an Element Is Not Found
22.67.3.SingleOrDefault after where clause
22.67.4.SingleOrDefault with object property reference
22.67.5.LastOrDefault: Where an Element Is Not Found