Csharp/C Sharp/LINQ/OrderBy
Версия от 15:31, 26 мая 2010; (обсуждение)
Содержание
- 1 an array of string values sorted first by length, then sorted alphabetically, using a case-insentive comparison.
- 2 First OrderBy Prototype
- 3 OrderBy: prints an alphabetically sorted version of a string array
- 4 OrderBy with customized Comparer
- 5 OrderBy with passing a lambda function
- 6 products sorted alphabetically by the product name
- 7 products sorted by the number of units of each product that are in stock
- 8 sorted alphabetically in descending order, using a case insensitive comparision.
- 9 string array sorted by the length each element
- 10 uses a compound orderby to sort a list of digits first by length of their name, and then alphabetically.
- 11 uses a compound orderby to sort a list of products, first by category, and then by unit price, from highest to lowest.
- 12 Where with OrderBy
an array of string values sorted first by length, then sorted alphabetically, using a case-insentive comparison.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class CaseInsensitiveComparer : IComparer<string> {
public int Compare(string x, string y) {
return string.rupare(x, y, true);
}
}
public class MainClass {
public static void Main() {
string[] words = { "a", "A", "b", "B", "C", "c" };
var sortedWords =
words.OrderBy(a => a.Length)
.ThenBy(a => a, new CaseInsensitiveComparer());
Console.Write(sortedWords);
}
}
First OrderBy Prototype
using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
public static void Main() {
string[] presidents = {"ant", "arding", "arrison", "eyes", "over", "ackson"};
IEnumerable<string> items = presidents.OrderBy(s => s.Length);
foreach (string item in items)
Console.WriteLine(item);
}
}
OrderBy: prints an alphabetically sorted version of a string array
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
string[] words = { "C", "a", "b" };
var sortedWords =
from w in words
orderby w
select w;
Console.WriteLine("The sorted list of words:");
foreach (var w in sortedWords) {
Console.WriteLine(w);
}
}
}
OrderBy with customized Comparer
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class CaseInsensitiveComparer : IComparer<string> {
public int Compare(string x, string y) {
return string.rupare(x, y, true);
}
}
public class MainClass {
public static void Main() {
string[] words = { "a", "A", "b", "B", "C", "c" };
var sortedWords = words.OrderBy(a => a, new CaseInsensitiveComparer());
}
}
OrderBy with passing a lambda function
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class CaseInsensitiveComparer : IComparer<string> {
public int Compare(string x, string y) {
return string.rupare(x, y, true);
}
}
public class MainClass {
public static void Main() {
string[] words = { "a", "A", "b", "B", "C", "c" };
var sortedWords = words.OrderBy(a => a, new CaseInsensitiveComparer());
}
}
products sorted alphabetically by the product name
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
List<Product> products = GetProductList();
var sortedProducts =
from p in products
orderby p.ProductName
select p;
Console.WriteLine(sortedProducts);
}
static List<Product> GetProductList() {
List<Product> empTree = new List<Product>();
empTree.Add(new Product { ProductName = "A", Category = "O", UnitPrice = 12, UnitsInStock = 5, Total = 36, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "B", Category = "O", UnitPrice = 2, UnitsInStock = 4, Total = 35, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "C", Category = "O", UnitPrice = 112, UnitsInStock = 3, Total = 34, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "D", Category = "O", UnitPrice = 112, UnitsInStock = 0, Total = 33, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "E", Category = "O", UnitPrice = 1112, UnitsInStock = 2, Total = 32, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "F", Category = "O", UnitPrice = 11112, UnitsInStock = 0, Total = 31, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
return empTree;
}
}
class Product : IComparable<Product> {
public string ProductName { get; set; }
public string Category { get; set; }
public int UnitPrice { get; set; }
public int UnitsInStock { get; set; }
public int Total { get; set; }
public DateTime OrderDate { get; set; }
public int Id { get; set; }
public override string ToString() {
return String.Format("Id: {0}, Name: {1} , Category: {3}", this.Id, this.ProductName, this.Category);
}
int IComparable<Product>.rupareTo(Product other) {
if (other == null)
return 1;
if (this.Id > other.Id)
return 1;
if (this.Id < other.Id)
return -1;
return 0;
}
}
products sorted by the number of units of each product that are in stock
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
List<Product> products = GetProductList();
var sortedProducts =
from p in products
orderby p.UnitsInStock descending
select p;
Console.Write(sortedProducts);
}
static List<Product> GetProductList() {
List<Product> empTree = new List<Product>();
empTree.Add(new Product { ProductName = "A", Category = "O", UnitPrice = 12, UnitsInStock = 5, Total = 36, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "B", Category = "O", UnitPrice = 2, UnitsInStock = 4, Total = 35, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "C", Category = "O", UnitPrice = 112, UnitsInStock = 3, Total = 34, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "D", Category = "O", UnitPrice = 112, UnitsInStock = 0, Total = 33, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "E", Category = "O", UnitPrice = 1112, UnitsInStock = 2, Total = 32, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "F", Category = "O", UnitPrice = 11112, UnitsInStock = 0, Total = 31, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
return empTree;
}
}
class Product : IComparable<Product> {
public string ProductName { get; set; }
public string Category { get; set; }
public int UnitPrice { get; set; }
public int UnitsInStock { get; set; }
public int Total { get; set; }
public DateTime OrderDate { get; set; }
public int Id { get; set; }
public override string ToString() {
return String.Format("Id: {0}, Name: {1} , Category: {3}", this.Id, this.ProductName, this.Category);
}
int IComparable<Product>.rupareTo(Product other) {
if (other == null)
return 1;
if (this.Id > other.Id)
return 1;
if (this.Id < other.Id)
return -1;
return 0;
}
}
sorted alphabetically in descending order, using a case insensitive comparision.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class CaseInsensitiveComparer : IComparer<string> {
public int Compare(string x, string y) {
return string.rupare(x, y, true);
}
}
public class MainClass {
public static void Main() {
string[] words = { "a", "A", "b", "B", "C", "c" };
var sortedWords = words.OrderByDescending(a => a, new CaseInsensitiveComparer());
}
}
string array sorted by the length each element
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
string[] words = { "abc", "bcd", "def" };
var sortedWords =
from w in words
orderby w.Length
select w;
Console.WriteLine("The sorted list of words (by length):");
foreach (var w in sortedWords) {
Console.WriteLine(w);
}
}
}
uses a compound orderby to sort a list of digits first by length of their name, and then alphabetically.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
string[] digits = { "zero", "one", "two", "three"};
var sortedDigits =
from d in digits
orderby d.Length, d
select d;
Console.WriteLine("Sorted digits:");
foreach (var d in sortedDigits) {
Console.WriteLine(d);
}
}
}
uses a compound orderby to sort a list of products, first by category, and then by unit price, from highest to lowest.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
List<Product> products = GetProductList();
var sortedProducts =
from p in products
orderby p.Category, p.UnitPrice descending select p;
foreach (var s in sortedProducts) {
Console.Write(s);
}
}
static List<Product> GetProductList() {
List<Product> empTree = new List<Product>();
empTree.Add(new Product { ProductName = "A", Category = "O", UnitPrice = 12, UnitsInStock = 5, Total = 36, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "B", Category = "O", UnitPrice = 2, UnitsInStock = 4, Total = 35, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "C", Category = "O", UnitPrice = 112, UnitsInStock = 3, Total = 34, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "D", Category = "O", UnitPrice = 112, UnitsInStock = 0, Total = 33, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "E", Category = "O", UnitPrice = 1112, UnitsInStock = 2, Total = 32, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
empTree.Add(new Product { ProductName = "F", Category = "O", UnitPrice = 11112, UnitsInStock = 0, Total = 31, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
return empTree;
}
}
class Product : IComparable<Product> {
public string ProductName { get; set; }
public string Category { get; set; }
public int UnitPrice { get; set; }
public int UnitsInStock { get; set; }
public int Total { get; set; }
public DateTime OrderDate { get; set; }
public int Id { get; set; }
public override string ToString() {
return String.Format("Id: {0}, Name: {1} , Category: {3}", this.Id, this.ProductName, this.Category);
}
int IComparable<Product>.rupareTo(Product other) {
if (other == null)
return 1;
if (this.Id > other.Id)
return 1;
if (this.Id < other.Id)
return -1;
return 0;
}
}
Where with OrderBy
using System;
using System.Collections.Generic;
using System.Linq;
public class MainClass {
public static void Main() {
string[] names = { "J", "P", "G", "Pa" };
IEnumerable<string> query = names.Where(n => n.Contains("a"))
.OrderBy(n => n.Length)
.Select(n => n.ToUpper());
}
}