How to Use Enum in C#

Enum is a typed constant that is specified for the new data form of Enumeration. An effective way to describe a set of named integral constants assigned to a variable is to include a Typesafe enumeration. Enums make the code more readable and less vulnerable to mistakes. If you have a set of functionally important and unchanged values, Enums are useful for developers.

Enums' key benefit is to make it possible in the future to adjust values. Enums are a robust alternative to the short String or Int constants used to describe sets of similar objects in far older APIs.

Sometimes we must use the constant variable in our application to not be changed throughout the application. One of the methods to declare the continuous variables are Enum. Let's discuss it.

Using Enum in C Sharp

Enum is the short form of Enumeration. Enum consumes less memory and space because they are value types, which means they store memory value. Also, Enums are strongly typed named constants.

Enums written by developers are used in the .NET system to develop numeric constants. A numeric value must be allocated to all the members of an enum. Here are the main points about Enums:

• In C#, Keyword Enums build enumerated types of data
• Enums are made for developers
• Enums are strongly typed constants, as described above.
• An enum of one form cannot be allocated automatically to another type of enum.
• Enum values are fixed

Enums are of two types in C#

Simple Enum - The members of this enum contain a single value.

Flags Enum - The members of this enum contain multiple values or multiple values combined using a bitwise OR operator. These enums are often used for bitwise operators.

Here we will talk about the Simple Enum only.

How to declare an Enum

Enum is declared by the enum keyword followed by the enum name and then its enum members. Like an example below

1public enum Vehicle
2{
3    Car,
4    Bike=3,
5    Truck,
6    Taxi,
7}

In the above code, an enum for the Vehicle is created. The enum values are started from 0 by default if we do not assign them the values and incremented by 1 for the next enum member.

That means the Car enum has the value 0 and the Bike enum assigned the value 3 that means the Bike enum now has the value 3 and the next enums are incremented by 1 means Truck and Taxi enum have the value 4 and 5 respectively.

By default, the type for enum elements is int. We can set different type by adding a colon like an example below.

1public enum Vehicle: byte
2{
3    Car,
4    Bike=3,
5    Truck,
6    Taxi,
7}

The different types which can be set are sbyte, byte, short, ushort, uint, ulong, and long.

Get the value of an Enum

To get the value of enum we can simply typecast it to its type. In the first example, the default type is int so we have to typecast it to int. Also, we can get the string value of that enum by using the ToString() method as below.

1Console.WriteLine((int)VehicleEnum.Car);
2string vehicle = Vehicle.Bike.ToString();
3Console.WriteLine(vehicle);

Output:

10
2Bike

Parse the string value into an Enum

For parsing the string value into enum we have 2 methods

1. Enum.Parse(Type enumType,string value) - This method directly parses the string representation of the name or numeric value of enum member into enumType object. If the string representation of the name is not found, then it will give the exception.

1Console.WriteLine(Enum.Parse(typeof(Vehicle),"Car"));

Output:

1Car

2. Enum.TryParse(string? value,out enumType result) - This method gives the result in bool value. if the string representation of the name or numeric value of enum member into enumType object is parsed, then the result will be true, and the parsed value will be in the out variable. If the string value is not parsed, then the result will be false.

1Enum.TryParse("0",out Vehicle value);
2Console.WriteLine(value);

Output:

1Car

Note - Both the methods also have overload methods.

Check if a string value is defined in the Enum

We can check if a given integral value, or its name as a string, exists in a specified enum.

1Console.WriteLine(Enum.IsDefined(typeof(Vehicle), 0));

OR

1Console.WriteLine(Enum.IsDefined(typeof(Vehicle), "car"));

Output:

1True

Loop through all the Enum

For looping through the enums you can write the below code -

1foreach (var data in Enum.GetNames(typeof(Vehicle)))
2{
3    Console.WriteLine(data+" - "+ (int)Enum.Parse(typeof(Vehicle), data));
4}

Here Enum.GetNames(Type enumType) method is used, which retrieves an array of the names from the specified enum.

Output:

1Car - 0
2Bike - 3
3Truck - 4
4Taxi - 5

Call an enum by the integral value

We can call the enum member by its integral value. If there is no corresponding value related to that integral value, then it will print that integral value.

1Console.WriteLine((Vehicle)3);

Output

1Bike

Conclusion

The advantages of using enums are that they are very easy to use and represented as strings but processed as integers. Enums are easy to maintain and improve code readability because they provide symbolic named constants, which means you need to remember the names, not the integer values.

If you want to learn more about C programming, here is another article written on C## Exceptions and Exception Handling in C# I hope you learn something new today and will going to try it out, if you have any questions feel free to drop a comment below.