C# | Type.GetEnumName() Method

Type.GetEnumName(Object) Method is used to return the name of the constant which has the specified value for the current enumeration type.

Syntax:

public virtual string GetEnumName (object value);

Here, it takes the value whose name is to be retrieved.
Return Value: This method returns the name of the member of the current enumeration type which has the specified value. If no such constant is found then it will return null.
Exceptions: 

• ArgumentException: If the current type is not an enumeration or value is neither of the current type nor does it have the same underlying type as the current type.
• ArgumentNullException: If value is null.

Below programs illustrate the use of the above-discussed method:
Example 1:

csharp

// C# program to demonstrate the
// Type.GetEnumName(Object) Method
using System;
using System.Globalization;
using System.Reflection;

class GFG {

    // Defining enum ABC
    enum ABC {A, B, C}

    // Main Method
    public static void Main()
    {

        // Creating try-catch block
        // to handle exceptions
        try {

            // Creating and initializing object
            // of ABC with instance of enum ABC
            ABC a = ABC.A;

            // Declaring and initializing
            // object of Type
            Type type = a.GetType();

            string obj = type.GetEnumName(a);

            Console.WriteLine("Name of constant is: " + obj);
        }

        // catch ArgumentNullException here
        catch (ArgumentNullException e)
        {
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

Output:

Name of constant is: A

Example 2: For ArgumentException

csharp

// C# program to demonstrate the
// Type.GetEnumName(Object) Method
using System;
using System.Globalization;
using System.Reflection;

class GFG {

    // Defining enum ABC
    enum ABC {A, B, C}

    // Main Method
    public static void Main()
    {

        // Creating try-catch block
        // to handle exceptions
        try {

            // Creating and initializing object
            // of ABC with instance of enum ABC
            ABC a = ABC.A;

            // Declaring and initializing
            // object of Type
            Type type = typeof(int);

            string obj = type.GetEnumName(a);

            Console.WriteLine("Name of constant is: " + obj);
        }

        // catch ArgumentNullException here
        catch (ArgumentNullException e)
        {
            Console.WriteLine("value is null. ");
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }

        // catch ArgumentException here
        catch (ArgumentException e)
        {
            Console.WriteLine("The current type is not an Enumeration.");
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

Output:

The current type is not an Enumeration.
Exception Thrown: System.ArgumentException

Example 3: For ArgumentNullException

csharp

// C# program to demonstrate the
// Type.GetEnumName(Object) Method
using System;
using System.Globalization;
using System.Reflection;

class GFG {

   // Defining enum ABC
    enum ABC {A, B, C}

    // Main Method
    public static void Main()
    {

        // Creating try-catch block
        // to handle exceptions
        try {

            // Creating and initializing object
            // of ABC with instance of enum ABC
            ABC a = ABC.A;

            // Declaring and initializing
            // object of Type
            Type type = typeof(int);

            string obj = type.GetEnumName(null);

            Console.WriteLine("Name of constant is " + obj);
        }

        // catch ArgumentNullException here
        catch (ArgumentNullException e)
        {
            Console.WriteLine("value is null. ");
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }

        // catch ArgumentException here
        catch (ArgumentException e)
        {
            Console.WriteLine("The current type is not an Enumeration.");
            Console.Write("Exception Thrown: ");
            Console.Write("{0}", e.GetType(), e.Message);
        }
    }
}

Output:

value is null. 
Exception Thrown: System.ArgumentNullException

Reference:

• https://docs.microsoft.com/en-us/dotnet/api/system.type.getenumname?view=netframework-4.8