using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
public static void Main() {
int[] intArray = new int[] { 1, 2, 3 };
List<int> ints = intArray.Select(i => i).ToList();
foreach (int i in ints)
Console.WriteLine(i);
intArray[0] = 5;
foreach (int i in ints)
Console.WriteLine(i);
}
}
Software Development
software development notes, main category for Cs, Java, and other programming experiences.
Demonstrating the Query Results Changing Between Enumerations
using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
public static void Main() {
int[] intArray = new int[] { 1, 2, 3 };
IEnumerable<int> ints = intArray.Select(i => i);
foreach (int i in ints)
Console.WriteLine(i);
intArray[0] = 5;
foreach (int i in ints)
Console.WriteLine(i);
}
}
Query with Intentional Exception Deferred Until Enumeration
using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
public static void Main() {
string[] strings = { "one", "two", null, "three" };
Console.WriteLine("Before Where() is called.");
IEnumerable<string> ieStrings = strings.Where(s => s.Length == 3);
Console.WriteLine("After Where() is called.");
foreach (string s in ieStrings) {
Console.WriteLine("Processing " + s);
}
}
}
Converting an Array of Strings to Integers and Sorting It
using System;
using System.Linq;
public class MainClass {
public static void Main() {
string[] numbers = { "0042", "010", "9", "2q7" };
int[] nums = numbers.Select(s => Int32.Parse(s)).OrderBy(s => s).ToArray();
foreach (int num in nums)
Console.WriteLine(num);
}
}
Converting an Array of Strings to Integers
using System;
using System.Linq;
public class MainClass {
public static void Main() {
string[] numbers = { "0042", "010", "9", "2q7" };
int[] nums = numbers.Select(s => Int32.Parse(s)).ToArray();
}
}
uses select to create a sequence of each product name.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
List
var productNames =
from p in products
select p.ProductName;
foreach (var productName in productNames) {
Console.WriteLine(productName);
}
}
static List
List
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
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
if (other == null)
return 1;
if (this.Id > other.Id)
return 1;
if (this.Id < other.Id) return -1; return 0; } } [/csharp]
Select with Anonymous Types: prints the name of every product in the product list along with the category of the product and its unit price
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
public static void Main() {
List
var productInfos =
from p in products
select new { p.ProductName, p.Category, Price = p.UnitPrice };
Console.WriteLine(“Product Info:”);
foreach (var productInfo in productInfos) {
Console.WriteLine(“{0} is in the category {1} and costs {2} per unit.”, productInfo.ProductName, productInfo.Category, productInfo.Price);
}
}
static List
List
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
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
if (other == null)
return 1;
if (this.Id > other.Id)
return 1;
if (this.Id < other.Id) return -1; return 0; } } [/csharp]