Collection represents a set of classes or objects
that you can access to different type for different purpose.
The name space of
collection classes are
1. System. Collections
2. System.Collections.Generic
2. System.Collections.Generic
The System.Collection class contain the many classes for different
purpose which explains in below.
- ArrayList
- Dictionary
- HashTable
- Stack
- Queue
ArrayList
Array List is collection with different data type
using the System.Collection namespace. It is dynamic array and provides the
feature for dynamic access.
Example for Add() method
using
System;
using
System.Collections;
using
System.Collections.Generic;
using
System.Linq;
using
System.Text;
namespace
CollectionClasses
{
public class Program
{
public static
void ArrayListColl()
{
ArrayList
objArrayList = new ArrayList();
objArrayList.Add("India");
objArrayList.Add("Uttar
Pradesh");
objArrayList.Add("Kushinagar");
foreach
(string element in objArrayList)
{
Console.WriteLine(element);
Console.ReadLine();
}
}
static void
Main(string[] args)
{
ArrayListColl();
}
}
}
Output
Again another example for RemoveAt() method
Remove the records with help of specific index.
using
System;
using
System.Collections;
using
System.Collections.Generic;
using
System.Linq;
using
System.Text;
namespace
CollectionClasses
{
public class Program
{
public static
void ArrayListColl()
{
ArrayList
objArrayList = new ArrayList();
objArrayList.Add("India");
objArrayList.Add("Uttar
Pradesh");
objArrayList.Add("Kushinagar");
objArrayList.RemoveAt(1);
foreach
(string element in objArrayList)
{
Console.WriteLine(element);
Console.ReadLine();
}
}
static void
Main(string[] args)
{
ArrayListColl();
}
}
}
Output
In the above example, remove the string from the
Array List at index 1. So output is below.
Again another example for Remove () method
Remove the records with help of specific object.
using
System;
using
System.Collections;
using
System.Collections.Generic;
using
System.Linq;
using
System.Text;
namespace
CollectionClasses
{
public class Program
{
public static
void ArrayListColl()
{
ArrayList
objArrayList = new ArrayList();
objArrayList.Add("India");
objArrayList.Add("Uttar
Pradesh");
objArrayList.Add("Kushinagar");
objArrayList.Remove("Kushinagar");
foreach
(string element in objArrayList)
{
Console.WriteLine(element);
Console.ReadLine();
}
}
static
void Main(string[] args)
{
ArrayListColl();
}
}
}
OutPut :
Again another example for Insert () method
Insert the records with help of specific index.
using
System;
using
System.Collections;
using
System.Collections.Generic;
using
System.Linq;
using
System.Text;
namespace
CollectionClasses
{
public class Program
{
public static
void ArrayListColl()
{
ArrayList
objArrayList = new ArrayList();
objArrayList.Insert(0,"India");
objArrayList.Insert(1,"Uttar
Pradesh");
objArrayList.Insert(2,"Kushinagar");
foreach
(string element in objArrayList)
{
Console.WriteLine(element);
Console.ReadLine();
}
}
static void
Main(string[] args)
{
ArrayListColl();
}
}
}
OupPut
Dictionary
The Dictionary collection class is a generic class
that contain the any data type. The Dictionary class contain two parameters
(generic type) one is key and other is value. Before implementation, we must
import the System.Collections.Generic namespace. The dictionary type provides
fast searching with key to get its values. Dictionary is used when we have
different elements. The Dictionary contains the some different feature.
Syntax :
Dictionary objDict=new Dictionary();
Example for Add, ContainsKey and ContainsValue
Example for Add, ContainsKey and ContainsValue
using
System;
using
System.Collections;
using
System.Collections.Generic;
using
System.Linq;
using
System.Text;
namespace
CollectionClasses
{
public class Program
{
public static
void DictionaryMethod()
{
Dictionary
objDict=new Dictionary();
objDict.Add("India",1);
objDict.Add("UP",2);
objDict.Add("Kushinagar",3);
if
(objDict.ContainsKey("India"))
{
dynamic
text = objDict["India"];
Console.WriteLine(text);
Console.ReadLine();
}
if
(objDict.ContainsValue(1))
{
Console.WriteLine("India");
Console.ReadLine();
}
}
static void
Main(string[] args)
{
DictionaryMethod();
}
}
}
OutPut :
Another example for dictionary KeyValuePair objects
using
System;
using
System.Collections;
using
System.Collections.Generic;
using
System.Linq;
using
System.Text;
namespace
CollectionClasses
{
public class Program
{
public static
void KeyValuePair()
{
dynamic
keyValList = new List>();
keyValList.Add(new
KeyValuePair("India", 1));
keyValList.Add(new
KeyValuePair("UP", 2));
keyValList.Add(new
KeyValuePair("Kushinagar", 4));
foreach
(var element in keyValList)
{
Console.WriteLine(element);
Console.ReadLine();
}
}
static void
Main(string[] args)
{
KeyValuePair();
}
}
}
OutPut :
Another example for KeyValuePair
using
System;
using
System.Collections;
using
System.Collections.Generic;
using
System.Linq;
using
System.Text;
namespace
CollectionClasses
{
public class Program
{
public static
void KeyValuePair()
{
Dictionary
keyValList = new Dictionary();
keyValList.Add("India",
1);
keyValList.Add("UP",
2);
keyValList.Add("Kushinagar",
4);
foreach
(KeyValuePair element in keyValList)
{
Console.WriteLine("key
= {0}, value = {1}", element.Key,element.Value);
}
Console.ReadKey();
}
static void
Main(string[] args)
{
KeyValuePair();
}
}
}
OutPut :
HashTable
HashTable is a collection classes which provide the
support to key base searching and stored the key value pair type collection
data. HashTable searching the element is very fast but slower then generic
Dictionary type. In HashTable we can maintain the data uniqueness that means
without having null values and duplicate value. In HashTable, both key and
value is object and we can retrieve the items from the HashTable by providing
the key.
Syntax :
Hashtable objHash=new Hashtable();
HashTable contain the methods which are give below in
HashTable contain the methods which are give below in
Simple example of HashTable
Simple example of HashTable
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace CollectionClasses
{
public
class Program
{
public
static void HashTableMethod()
{
Hashtable objHash=new Hashtable();
objHash.Add("India", 1);
objHash.Add("UP", 2);
objHash.Add("Kushinagar", 4);
foreach (DictionaryEntry element in objHash)
{
Console.WriteLine("key
= {0}, value = {1}", element.Key,element.Value);
}
Console.ReadKey();
}
static
void Main(string[] args)
{
HashTableMethod();
}
}
}
OutPut :
AAnother example to get the keys using HashTable
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace CollectionClasses
{
public
class Program
{
public
static void HashTableMethod()
{
Hashtable objHash=new Hashtable();
objHash.Add("India", 1);
objHash.Add("UP", 2);
objHash.Add("Kushinagar", 4);
IDictionaryEnumerator
objDe = objHash.GetEnumerator();
while
(objDe.MoveNext())
{
string
result = objDe.Key.ToString();
Console.WriteLine(result);
}
Console.ReadKey();
}
static
void Main(string[] args)
{
HashTableMethod();
}
}
}
OutPut :
Another example to get the values using HashTable
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
namespace CollectionClasses
{
public
class Program
{
public
static void HashTableMethod()
{
Hashtable objHash=new Hashtable();
objHash.Add("India", 1);
objHash.Add("UP", 2);
objHash.Add("Kushinagar", 4);
IDictionaryEnumerator
objDe = objHash.GetEnumerator();
while
(objDe.MoveNext())
{
string
result = objDe.Value.ToString();
Console.WriteLine(result);
}
Console.ReadKey();
}
static
void Main(string[] args)
{
HashTableMethod();
}
}
}
OutPut :
Stack
Stack is a Last-In-First-Out collection that is called LIFO. Stack is a
generic type collection. Stack worked on two basic components which are 1. Push
2. Pop Push is formally worked for insert an item on the top in stack. Pop is
formally worked on the remove the last inserted record from the stack.
Example for Push
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace CollectionClasses
{
public
class Program
{
public
static Stack StackMethod()
{
Stack
objStack = new Stack();
objStack.Push(1);
objStack.Push(10);
objStack.Push(100);
objStack.Push(1000);
objStack.Push(10000);
return
objStack;
}
static
void Main(string[] args)
{
dynamic
stack= StackMethod();
foreach
(int item in stack)
{
Console.WriteLine(item);
}
Console.ReadLine();
}
}
}
OutPut :
Another example for Pop
namespace CollectionClasses
{
public
class Program
{
public
static Stack StackMethod()
{
Stack
objStack = new Stack();
objStack.Push(1);
objStack.Push(10);
objStack.Push(100);
objStack.Push(1000);
objStack.Push(10000);
return
objStack;
}
static
void Main(string[] args)
{
Stack
stack= StackMethod();
int
pop= stack.Pop();
Console.WriteLine(pop);
Console.ReadLine();
}
}
}
OutPut :
Example using Push, Pop and Peek
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace CollectionClasses
{
public
class Program
{
public
static Stack StackMethod()
{
Stack
objStack = new Stack();
objStack.Push(1);
objStack.Push(10);
objStack.Push(100);
objStack.Push(1000);
objStack.Push(10000);
return
objStack;
}
static
void Main(string[] args)
{
Stack
stack= StackMethod();
Console.WriteLine("Display
the Stack");
foreach
(int i in stack)
{
Console.WriteLine(i);
}
int
pop = stack.Pop();
Console.WriteLine("pop
the element from the stack!");
Console.WriteLine(pop);
int
peek= stack.Peek();
Console.WriteLine("peek
the element from the stack!");
Console.WriteLine(peek);
Console.ReadLine();
}
}
}
The Output as given below
Queue
Queue is First-In-First-Out collection that is classed FIFO. Queue is a
generic collection. Queue provides the First - come first- service.
Example
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace CollectionClasses
{
public
class Program
{
public
static Queue QueueMethod()
{
//
Add integers to queue.
Queue
objQueue = new Queue();
objQueue.Enqueue(1);
objQueue.Enqueue(10);
objQueue.Enqueue(100);
objQueue.Enqueue(1000);
//
Loop through queue.
foreach
(int i in objQueue)
{
Console.WriteLine(i);
}
return
objQueue;
}
static
void Main(string[] args)
{
Queue
queu = QueueMethod();
Console.WriteLine(queu);
Console.ReadLine();
}
}
}
The Output as given below
|
Anil Singh is an author, tech blogger, and software programmer. Book writing, tech blogging is something do extra and Anil love doing it. For more detail, kindly refer to this link..
|