в 15:31, 26 мая 2010

2010-05-26T15:31:53Z

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2010-05-26T12:18:12Z

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==Query a list of objects by its property==

<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 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; }
}
}
class Role {
int _id;
string role;
public int ID {
get { return _id; }
set { _id = value; }
}
public string Role {
get { return role; }
set { role = value; }
}
}
class Program {
static void Main(string[] args) {
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"}
};
List<Role> roles = new List<Role> {
new Role { ID = 1, Role = "Manager" },
new Role { ID = 2, Role = "Developer" }
};

var query = people
.Where(p => p.ID == 1)
.Select(p => new { p.FirstName, p.LastName });
}
}</source>

==Query an array of object by its property value==

<source lang="csharp">using System;
using System.Collections.Generic;
using System.Linq;
using System.Drawing;
public class Book {
public String Title { get; set; }
public override String ToString() {
return Title;
}
}
class Program {
static void Main(string[] args) {
Book[] books = {
new Book { Title="A" },
new Book { Title="F" },
new Book { Title="E" } };
var titles =
books
.Where(book => book.Title.Contains("A"))
.Select(book => book.Title);
}
}</source>

==Query by Person"s FirstName==

<source lang="csharp">using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Linq;
using System.Reflection;
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"},
new Person { ID = 3, IDRole = 2, LastName = "G", FirstName = "M"},
new Person { ID = 4, IDRole = 3, LastName = "C", FirstName = "G"}
};
var query = from p in people
where p.FirstName == "B"
select p;
}
}</source>

==Select object in a List==

<source lang="csharp">using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Linq;
using System.Reflection;
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"},
new Person { ID = 3, IDRole = 2, LastName = "G", FirstName = "M"},
new Person { ID = 4, IDRole = 3, LastName = "C", FirstName = "G"}
};
var query = from p in people select p;
}
}</source>

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в 15:31, 26 мая 2010

Admin: 1 версия