Check if the Hashtable contains a specific value in C#

To check if the Hashtable contains a specific value, the code is as follows −

Example

 Live Demo

using System; using System.Collections; public class Demo {    public static void Main(){       Hashtable hash = new Hashtable();       hash.Add("1", "A");       hash.Add("2", "B");       hash.Add("3", "C");       hash.Add("4", "D");       hash.Add("5","E");       hash.Add("6", "F");       hash.Add("7", "G");       hash.Add("8","H");       hash.Add("9", "I");       hash.Add("10", "J");       Console.WriteLine("Hashtable Key and Value pairs...");       foreach(DictionaryEntry entry in hash){          Console.WriteLine("{0} and {1} ", entry.Key, entry.Value);       }       Console.WriteLine("Is Hashtable having fixed size? = "+hash.IsFixedSize);       Console.WriteLine("If Hashtable read-only? = "+hash.IsReadOnly);       Console.WriteLine("The Hashtable consists of the value? = "+hash.ContainsValue("H"));    } }

Output

This will produce the following output −

Hashtable Key and Value pairs... 10 and J 1 and A 2 and B 3 and C 4 and D 5 and E 6 and F 7 and G 8 and H 9 and I Is Hashtable having fixed size? = False If Hashtable read-only? = False The Hashtable consists of the value? = True

Example

Let us see another example −

 Live Demo

using System; using System.Collections; public class Demo {    public static void Main(){       Hashtable hash = new Hashtable();       hash.Add("One", "Katie");       hash.Add("Two", "John");       hash.Add("Three", "Barry");       hash.Add("Four", "Mark");       hash.Add("Five","Harry");       hash.Add("Six", "Nathan");       hash.Add("Seven", "Tom");       hash.Add("Eight","Andy");       hash.Add("Nine", "Illeana");       hash.Add("Ten", "Tim");       Console.WriteLine("Hashtable Key and Value pairs...");       foreach(DictionaryEntry entry in hash){          Console.WriteLine("{0} and {1} ", entry.Key, entry.Value);    }       Console.WriteLine("Is Hashtable having fixed size? = "+hash.IsFixedSize);       Console.WriteLine("If Hashtable read-only? = "+hash.IsReadOnly);       Console.WriteLine("The Hashtable consists of the key? = "+hash.ContainsKey("Seven"));       Console.WriteLine("The Hashtable consists of the value? = "+hash.ContainsValue("Illeana"));    } }

Output

This will produce the following output −

Hashtable Key and Value pairs... One and Katie Ten and Tim Five and Harry Three and Barry Seven and Tom Two and John Four and Mark Eight and Andy Nine and Illeana Six and Nathan Is Hashtable having fixed size? = False If Hashtable read-only? = False The Hashtable consists of the key? = True The Hashtable consists of the value? = True