C# | Dictionary.ContainsValue() Method

This method is used to check whether the Dictionary<TKey,TValue> contains a specific value or not.

Syntax:

public bool ContainsValue (TValue value);

Here, the value is the Value to locate in the Dictionary. The value can be null for reference types.

Return Value: This method returns true if the Dictionary contains an element with the specified value otherwise it returns false.

Below are the programs to illustrate the use of Dictionary<TKey,TValue>.ContainsValue() Method:

Example 1:

// C# code to check if a value
// is present or not in a Dictionary.
using System;
using System.Collections.Generic;

class GFG {

    // Driver code
    public static void Main()
    {

        // Create a new dictionary of
        // strings, with string keys.
        Dictionary<string, string> myDict =
          new Dictionary<string, string>();

        // Adding key/value pairs in myDict
        myDict.Add("Australia", "Canberra");
        myDict.Add("Belgium", "Brussels");
        myDict.Add("Netherlands", "Amsterdam");
        myDict.Add("China", "Beijing");
        myDict.Add("Russia", "Moscow");
        myDict.Add("India", "New Delhi");

        // Checking the value "India" but
        // here "India" is the key
        if (myDict.ContainsValue("India"))
            Console.WriteLine("Value : India is present.");

        else
            Console.WriteLine("Value : India is not present.");
    }
}

Output:

Value : India is not present.

Example 2:

// C# code to check if a value is
// present or not in a Dictionary.
using System;
using System.Collections.Generic;

class GFG {

    // Driver code
    public static void Main()
    {

        // Create a new dictionary of
        // strings, with string keys.
        Dictionary<string, string> myDict =
           new Dictionary<string, string>();

        // Adding key/value pairs in myDict
        myDict.Add("Australia", "Canberra");
        myDict.Add("Belgium", "Brussels");
        myDict.Add("Netherlands", "Amsterdam");
        myDict.Add("China", "Beijing");
        myDict.Add("Russia", "Moscow");
        myDict.Add("India", "New Delhi");

        // Checking for value Moscow
        if (myDict.ContainsValue("Moscow"))
            Console.WriteLine("Value : Moscow is present");

        else
            Console.WriteLine("Value : Moscow is absent");
    }
}

Output:

Value : Moscow is present

Reference:

• https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.dictionary-2.containsvalue?view=netframework-4.7.2