в 15:31, 26 мая 2010

2010-05-26T15:31:18Z

Admin: 1 версия

2010-05-26T11:38:30Z

1 версия

Новая страница

==Calling the ToList Operator==

<source lang="csharp">
using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
public static void Main() {
string[] presidents = {"G", "H", "a", "H", "over", "Jack"};
List<string> names = presidents.ToList();
foreach (string name in names)
Console.WriteLine(name);
}
}
</source>

==calling ToList.==

<source lang="csharp">
using System;
using System.Collections.Generic;
using System.Linq;
public class MainClass {
public static void Main() {
var numbers = new List<int>() { 1, 2 };
List<int> timesTen = numbers
.Select(n => n * 10)
.ToList();
numbers.Clear();
Console.WriteLine(timesTen.Count);
}
}
</source>

==Convert an ArrayList to an IEnumerable<T> That Can Be Used with the Typical Standard Query Operators==

<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() {
ArrayList employees = Employee.GetEmployeesArrayList();
Console.WriteLine("The data type of employees is " + employees.GetType());
var seq = employees.Cast<Employee>();
Console.WriteLine("The data type of seq is " + seq.GetType());
var emps = seq.OrderBy(e => e.lastName);
foreach (Employee emp in emps)
Console.WriteLine("{0} {1}", emp.firstName, emp.lastName);
}
}
</source>

==Convert Query result to a List==

<source lang="csharp">
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Linq;
class Employee {
int _id;
int _idRole;
string _lastName;
string _firstName;
public int ID {
get { return _id; }
set { _id = value; }
}
public int IDRole {
get { return _idRole; }
set { _idRole = value; }
}
public string LastName {
get { return _lastName; }
set { _lastName = value; }
}
public string FirstName {
get { return _firstName; }
set { _firstName = value; }
}
}
public class MainClass {
public static void Main() {
List<Employee> people = new List<Employee> {
new Employee { ID = 1, IDRole = 1, LastName = "A", FirstName = "B"},
new Employee { ID = 2, IDRole = 2, LastName = "G", FirstName = "T"}
};
var query = from p in people
where p.LastName.Length == 4
select p.LastName;
List<string> names = query.ToList<string>();
Console.Write(names);
}
}
</source>

← Предыдущая	Версия 15:31, 26 мая 2010
(нет различий)

Csharp/C Sharp/LINQ/ToList - История изменений

в 15:31, 26 мая 2010

Admin: 1 версия