Enumeration

Create an Enum

An enumeration or rather Enum, allows you to restrict your set of options into values that are relevant.

Why use an Enum?
In a situation where we need to create a departmental application, e.g a Software Organization with Developers from different fields: Such as .Net developer, Java Developer, Ruby Developer, etc, In this case, it would be better to use an Enum (and not a magic string) to organize the types we have among this developers within the organization.



Example 1:


       protected void Button1_Click(object sender, EventArgs e)
        {
            var developer = new Engineer();
            hero.Name = heroNameTextBox.Text;



            EngineerType selection;

            if(Enum.TryParse(heroTypeDropDownList.SelectedValue, out selection))
            {
                hero.Type = selection;
            }
            resultLabel.Text += "You selected a " + selection + "!";
        }
    }
    public class Engineer
    {
        public string Name { get; set; }
        public EngineerType Type { get; set; }
    }
    public enum EngineerType
    {
        dotNet,
        Java,
        Csharp,
        C,
    }
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Diagram showing Enumeration Application 

Example 2

Create a Pet class that uses enum Type for the Pet types instead of a String for the Pet Type.

namespace EnumerationLesson
{
    public class Pet
    {
          public string Name { get; set; }
          public int Age { get; set; }
            //public string Type { get; set; } // Replaced with PetType Type
          public PetType Type { get; set; }
          private StringBuilder _sb;
            //public Pet(string Name, int Age, string Type)
         public Pet(string Name, int Age, PetType Type)
        {
            this.Name = Name;
            this.Age = Age;
            this.Type = Type;
           _sb = new StringBuilder();
        }
 //Create an enum PetType and replace the string identifier for Type property to PetType.
 // Here is how you create an enum:
        public enum PetType
        {
            dog,
            snake,
            cat,
            tortoise,
         }
       
 Learn also: How to create database

Happy coding!

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