In this blog, I’m trying to explain the concept of hash table in c#.

The Hashtable class represents a collection of key-and-value pairs that are organized based on the hash code of the key. It uses the key to access the elements in the collection.

A hash table is used when you need to access elements by using key, and you can identify a useful key value. Each item in the hash table has a key/value pair. The key is used to access the items in the collection.

Creating hash table
Hashtable ht =new Hashtable();
This code will create hash table with named ht.
Adding items to hash table



This code will add items to hash table, it uses add() method and has key and value parameters.

Retrieving an item value in hash table

string name=ht[001].ToString();

This code will retrieve the item value.

Removing item from hash table


This code will remove the item from the hash table with key value 001.


using System;
using System.Collections;
namespace HashTableConsoleApplication
    class Program
        static void Main(string[] args)
            Hashtable ht = new Hashtable();
            Console.Write("Enter Maximum Number Of Record To Be In Hashtable = ");
            int max = Convert.ToInt32(Console.ReadLine());
            for (int i = 1; i <= max; i++)
                Console.Write("Enter Data =");
                string data = Console.ReadLine();
                ht.Add(i, data);
            ICollection key = ht.Keys;
            Console.WriteLine("\n\nData in Hashtable");
            foreach (int k in key)
                Console.WriteLine(k + ":" + ht[k]);


  Modified On Sep-18-2014 01:24:13 PM

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