в 15:31, 26 мая 2010

2010-05-26T15:31:18Z

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2010-05-26T11:38:24Z

1 версия

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==ElementAtOrDefault Operator with an Invalid Index==

<source lang="csharp">
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().ElementAtOrDefault(5);
Console.WriteLine(emp == null ? "NULL" : string.Format("{0} {1}", emp.firstName, emp.lastName));
}
}
</source>

==ElementAtOrDefault Operator with a Valid Index==

<source lang="csharp">
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().ElementAtOrDefault(3);
Console.WriteLine(emp == null ? "NULL" :string.Format("{0} {1}", emp.firstName, emp.lastName));
}
}
</source>

==use ElementAtOrDefault==

<source lang="csharp">
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Linq;
public class MainClass{
public static void Main(){
int[] numbers = {1, 2, 3, 4, 5, 6, 7, 8, 9};
var query = numbers.ElementAtOrDefault(9);
Console.Write(query);
}
}
</source>

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в 15:31, 26 мая 2010

Admin: 1 версия