Csharp/C Sharp/Language Basics/Foreach
Содержание
[убрать]- 1 a foreach loop
- 2 ArrayList foreach
- 3 Foreach for arraylist
- 4 Hashtable and foreach
- 5 Queue enqueue and foreach
- 6 Search an array using foreach
- 7 Stack push and foreach
- 8 Sums the values in an array using a foreach loop
- 9 Use break with a foreach
- 10 Use foreach on a two-dimensional array
- 11 Use the foreach loop
a foreach loop
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example4_12.cs illustrates the use of
a foreach loop
*/
public class Example4_12
{
public static void Main()
{
int [] myValues = {2, 4, 3, 5, 1};
foreach (int counter in myValues)
{
System.Console.WriteLine("counter = " + counter);
}
}
}
ArrayList foreach
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
*/
using System;
using System.Collections;
namespace Client.Chapter_4___Program_Control
{
public class ForEaches
{
static void Main(string[] args)
{
ArrayList a = new ArrayList(10);
foreach (int x in a)
{
Console.WriteLine(x);
}
}
}
}
Foreach for arraylist
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
*/
using System;
using System.Collections;
namespace Client.Chapter_3___Structs__Enums__Arrays_and_Classes
{
public class MyArrayList
{
static void Main(string[] args)
{
ArrayList a = new ArrayList(10);
ArrayList.Synchronized(a);
int x = 0;
a.Add(x);
a.Insert(1, ++x);
foreach (int y in a)
{
Console.WriteLine(y);
}
a.Remove(x);
a.RemoveAt(0);
a.Clear();
}
}
}
Hashtable and foreach
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
*/
using System;
using System.Collections;
namespace Client.Chapter_3___Structs__Enums__Arrays_and_Classes
{
public class HashTablesChapter_3___Structs__Enums__Arrays_and_Classes
{
static void Main(string[] args)
{
Hashtable a = new Hashtable(10);
Hashtable.Synchronized(a);
a.Add(100, "Arrays");
a.Add(200, "Classes");
foreach(DictionaryEntry d in a)
{
Console.WriteLine(d.Value);
}
a.Remove(100);
a.Remove(200);
a.Clear();
}
}
}
Queue enqueue and foreach
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
*/
using System;
using System.Collections;
namespace Client.Chapter_3___Structs__Enums__Arrays_and_Classes
{
public class QueuesChapter_3___Structs__Enums__Arrays_and_Classes
{
static void Main(string[] args)
{
Queue a = new Queue(10);
int x = 0;
a.Enqueue(x);
x++;
a.Enqueue(x);
foreach (int y in a)
{
Console.WriteLine(y);
}
a.Dequeue();
a.Clear();
}
}
}
Search an array using foreach
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Search an array using foreach.
using System;
public class Search {
public static void Main() {
int[] nums = new int[10];
int val;
bool found = false;
// give nums some values
for(int i = 0; i < 10; i++)
nums[i] = i;
val = 5;
// use foreach to search nums for key
foreach(int x in nums) {
if(x == val) {
found = true;
break;
}
}
if(found)
Console.WriteLine("Value found!");
}
}
Stack push and foreach
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
*/
using System;
using System.Collections;
namespace Client.Chapter_3___Structs__Enums__Arrays_and_Classes
{
public class StacksChapter_3___Structs__Enums__Arrays_and_Classes
{
static void Main(string[] args)
{
Stack a = new Stack(10);
int x = 0;
a.Push(x);
x++;
a.Push(x);
foreach (int y in a)
{
Console.WriteLine(y);
}
a.Pop();
a.Clear();
}
}
}
Sums the values in an array using a foreach loop
/*
C# Programming Tips & Techniques
by Charles Wright, Kris Jamsa
Publisher: Osborne/McGraw-Hill (December 28, 2001)
ISBN: 0072193794
*/
// ForEach.cs -- Sums the values in an array using a foreach loop
//
// Compile this program with the folowing command line
// C:>csc ForEach.cs
//
namespace nsForEach
{
using System;
public class ForEach
{
static public void Main ()
{
DateTime now = DateTime.Now;
Random rand = new Random ((int) now.Millisecond);
int [] Arr = new int [10];
for (int x = 0; x < Arr.Length; ++x)
{
Arr[x] = rand.Next () % 100;
}
int Total = 0;
Console.Write ("Array values are ");
foreach (int val in Arr)
{
Total += val;
Console.Write (val + ", ");
}
Console.WriteLine ("and the average is {0,0:F1}",
(double) Total / (double) Arr.Length);
}
}
}
Use break with a foreach
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Use break with a foreach.
using System;
public class ForeachDemo1 {
public static void Main() {
int sum = 0;
int[] nums = new int[10];
// give nums some values
for(int i = 0; i < 10; i++)
nums[i] = i;
// use foreach to display and sum the values
foreach(int x in nums) {
Console.WriteLine("Value is: " + x);
sum += x;
if(x == 4) break; // stop the loop when 4 is obtained
}
Console.WriteLine("Summation of first 5 elements: " + sum);
}
}
Use foreach on a two-dimensional array
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Use foreach on a two-dimensional array.
using System;
public class ForeachDemo2 {
public static void Main() {
int sum = 0;
int[,] nums = new int[3,5];
// give nums some values
for(int i = 0; i < 3; i++)
for(int j=0; j < 5; j++)
nums[i,j] = (i+1)*(j+1);
// use foreach to display and sum the values
foreach(int x in nums) {
Console.WriteLine("Value is: " + x);
sum += x;
}
Console.WriteLine("Summation: " + sum);
}
}
Use the foreach loop
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Use the foreach loop.
using System;
public class ForeachDemo {
public static void Main() {
int sum = 0;
int[] nums = new int[10];
// give nums some values
for(int i = 0; i < 10; i++)
nums[i] = i;
// use foreach to display and sum the values
foreach(int x in nums) {
Console.WriteLine("Value is: " + x);
sum += x;
}
Console.WriteLine("Summation: " + sum);
}
}