в 15:31, 26 мая 2010

2010-05-26T15:31:18Z

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2010-05-26T11:38:39Z

1 версия

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==Calling the Common Library Filter Method==

<source lang="csharp">
using System.Collections;
using System;
public delegate bool IntFilter(int i);
public class MainClass {
public static void Main() {
int[] nums = { 1, 2, 3, 4, 5, 6};
int[] oddNums = FilterArrayOfInts(nums, IsOdd);
foreach (int i in oddNums)
Console.WriteLine(i);
}
public static bool IsOdd(int i) {
return ((i & 1) == 1);
}
public static int[] FilterArrayOfInts(int[] ints, IntFilter filter) {
ArrayList aList = new ArrayList();
foreach (int i in ints) {
if (filter(i)) {
aList.Add(i);
}
}
return ((int[])aList.ToArray(typeof(int)));
}
}
</source>

==Calling the Filter Method with a Lambda Expression==

<source lang="csharp">
using System;
using System.Collections;
public delegate bool IntFilter(int i);
public class MainClass {
public static int[] FilterArrayOfInts(int[] ints, IntFilter filter) {
ArrayList aList = new ArrayList();
foreach (int i in ints) {
if (filter(i)) {
aList.Add(i);
}
}
return ((int[])aList.ToArray(typeof(int)));
}
public static void Main() {
int[] nums = { 1, 2, 3, 4, 5};
int[] oddNums = FilterArrayOfInts(nums, i => ((i & 1) == 1));
foreach (int i in oddNums)
Console.WriteLine(i);
}
}
</source>

==Calling the Filter Method with an Anonymous Method==

<source lang="csharp">
using System;
using System.Collections;
public delegate bool IntFilter(int i);
public class MainClass {
public static int[] FilterArrayOfInts(int[] ints, IntFilter filter) {
ArrayList aList = new ArrayList();
foreach (int i in ints) {
if (filter(i)) {
aList.Add(i);
}
}
return ((int[])aList.ToArray(typeof(int)));
}
public static void Main() {
int[] nums = { 1, 2, 3, 4, 5, 6};
int[] oddNums = FilterArrayOfInts(nums, delegate(int i) { return ((i & 1) == 1); });
foreach (int i in oddNums)
Console.WriteLine(i);
}
}
</source>

==Use delegate to create a filter==

<source lang="csharp">
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Reflection;
using System.Linq;
using System.Xml;
using System.Xml.Linq;
class Person {
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; }
}
}
class Program {
static void Main(string[] args) {
List<Person> people = new List<Person> {
new Person { ID = 1, IDRole = 1, LastName = "A", FirstName = "B"},
new Person { ID = 2, IDRole = 2, LastName = "G", FirstName = "T"}
};
Func<Person, bool> filter = delegate(Person p) { return p.ID == 1; };
var query = people
.Where(filter)
.Select(p => new { p.FirstName, p.LastName });
}
}
</source>

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в 15:31, 26 мая 2010

Admin: 1 версия