C# Properties (GET, SET)

In c#, Property is an extension of the class variable. It provides a mechanism to read, write, or change the class variable's value without affecting the external way of accessing it in our applications.

In c#, properties can contain one or two code blocks called accessors, and those are called a get accessor and set accessor. By using get and set accessors, we can change the internal implementation of class variables and expose them without affecting the external way of accessing it based on our requirements.

Generally, in object-oriented programming languages like c#, you need to define fields as private and then use properties to access their values in a public way with get and set accessors.

Following is the syntax of defining a property with get and set accessor in c# programming language.

<access_modifier> <return_type> <property_name>
 {
    get
    {
       //Return the property value
    }
    set
    {
      //Set a new value
    }
 }

If you observe the above syntax, we used an access modifier and return type to define a property along with get and set accessors to make required modifications to the class variables based on our requirements.

Here, the get accessor code block will be executed whenever the property is read, and the code block of set accessor will be executed whenever the property is assigned to a new value.

In c#, the properties are categorized into three types, those are.

Type	Description
Read-Write	A property that contains a both `get` and `set` accessors, then we will call it a read-write property.
Read-Only	A property that contains only `get` accessor, then we will call it a read-only property.
Write-Only	A property that contains only `set` accessor, then we will call it a write-only property.

In c#, Properties won’t accept any parameters, and we should not pass a property as a ref or out parameter in our application.

Following is a simple example of defining a private variable and a property in the c# programming language.

class User
 {
    private string name;
    public string Name
    {
        get { return name; }
        set { name = value; }
    }
 }

If you observe the above example, we defined a property called “Name” and we used a get accessor to return a property value and set accessors to set a new value. Here, the value keyword in set accessor is used to define a value that is being assigned by set accessor.

In c#, the get accessor needs to be used only to return the field value or to compute it and return it, but we should not use it for changing the state of an object.

As discussed, we can extend the behavior of class variables using properties get and set accessors. Following is the example of extending the behavior of private variable in property using get and set accessors in c# programming language.

class User
 {
    private string name = "Suresh Dasari";
    public string Name
    {
      get
      {
          return name.ToUpper();
      }
      set
      {
          if (value == "Suresh")
             name = value;
      }
    }
 }

If you observe the above example, we are extending the behavior of private variable name using a property called Name with get and set accessors by performing some validations like making sure the Name value equals to only “Suresh” using set accessor and converting property text to uppercase with get accessor.

Here the field “name” is marked as private, so if you want to make any changes to this field, we can do it only by calling the property (Name).

In c# properties, the get accessor will be invoked while reading the value of a property, and when we assign a new value to the property, then the set accessor will be invoked by using an argument that provides the new value.

Following is an example of invoking get and set accessors of properties in c# programming language.

User u = new User();
 u.Name = "Rohini"; // set accessor will invoke
 Console.WriteLine(u.Name); // get accessor will invoke

In the above example, when we assign a new value to the property, then the set accessor will be invoked and the get accessor will be invoked when we try to read the value from the property.

C# Properties (Get, Set) Example

Following is an example of defining properties with get and set accessors to implement required validations without affecting the external way of using it in the c# programming language.

using System;

 namespace Tutlane
 {
     class User
     {
        private string location;
        private string name = "Suresh Dasari";
        public string Location
        {
            get { return location; }
            set { location = value; }
        }
        public string Name
        {
           get
           {
               return name.ToUpper();
           }
           set
           {
               if (value == "Suresh")
                  name = value;
           }
        }
     }
     class Program
     {
        static void Main(string[] args)
        {
            User u = new User();
            // set accessor will invoke
            u.Name = "Rohini";
            // set accessor will invoke
            u.Location = "Hyderabad";
            // get accessor will invoke
            Console.WriteLine("Name: " + u.Name);
            // get accessor will invoke
            Console.WriteLine("Location: " + u.Location);
            Console.WriteLine("\nPress Enter Key to Exit..");
            Console.ReadLine();
        }
     }
 }

If you observe the above example, we are extending the behavior of private variables (name, location) using properties (Name, Location) with get and set accessors by performing some validations like making sure Name value equals to only “Suresh” using set accessor and converting property text to uppercase with get accessor.

When you execute the above c# program, we will get the result below.

C# Properties (Get, Set) Example Result

If you observe the above example, our variable text converted to upper case, and even after we set the variable text as “Rohini”, it displayed text as “Suresh Dasari” because of the set accessor validation fails in the property.

C# Create Read-Only Properties

As discussed, if a property contains the only get accessor, then we will call it a read-only property. Following is the example of creating read-only properties in the c# programming language.

using System;

 namespace Tutlane
 {
    class User
    {
       private string name;
       private string location;
       public User(string a, string b)
       {
          name = a;
          location = b;
       }
       public string Name
       {
          get
          {
             return name;
          }
       }
       public string Location
       {
          get
          {
             return location;
          }
       }
    }
    class Program
    {
       static void Main(string[] args)
       {
           User u = new User("Suresh Dasari", "Hyderabad");
           // compile error
           // u.Name = "Rohini";
           // get accessor will invoke
           Console.WriteLine("Name: " + u.Name);
           // get accessor will invoke
           Console.WriteLine("Location: " + u.Location);
           Console.WriteLine("\nPress Enter Key to Exit..");
           Console.ReadLine();
       }
    }
 }

If you observe the above example, we created properties using only get accessor to make the properties read-only based on our requirements.

If we uncomment the commented code, we will get a compile error because our Name property doesn’t contain any set accessor to set a new value. It’s just read-only property.

When you execute the above c# program, you will get a result as shown below.

C# Create Readonly Properties Example Result

This is how we can create read-only properties in c# applications based on our requirements.

C# Create Write Only Properties

As discussed, if a property contains the only set accessor, then we will call it a write-only property. Following is the example of creating write-only properties in the c# programming language.

using System;

 namespace Tutlane
 {
     class User
     {
        private string name;
        public string Name
        {
           set
           {
              name = value;
           }
        }
        private string location;
        public string Location
        {
            set
            {
                location = value;
            }
        }
        public void GetUserDetails()
        {
           Console.WriteLine("Name: " + name);
           Console.WriteLine("Location: " + location);
        }
     }
     class Program
     {
         static void Main(string[] args)
         {
              User u = new User();
              u.Name = "Suresh Dasari";
              u.Location = "Hyderabad";
              // compile error
              //Console.WriteLine(u.Name);
              u.GetUserDetails();
              Console.WriteLine("\nPress Enter Key to Exit..");
              Console.ReadLine();
         }
     }
 }

If you observe the above example, we created properties using only set accessor to make the properties are write-only based on our requirements.

If we uncomment the commented code, then we will get a compile error because our Name property doesn’t contain any get accessor to return a value. It’s a just write-only property.

When you execute the above c# program, you will get a result like as shown below.

C# Create WriteOnly Properties Example Result

This is how we can create write-only properties in c# applications based on our requirements.

C# Auto Implemented Properties

In c#, a property is called an auto-implemented property when it contains accessors (get, set) without having any logic implementation.

Generally, the auto-implemented properties are useful whenever there is no logic implementation required in property accessors.

Following is the example of creating auto-implemented properties in the c# programming language.

using System;

 namespace Tutlane
 {
     class User
     {
        public string Name { get; set; }
        public string Location { get; set; }
     }
     class Program
     {
         static void Main(string[] args)
         {
             User u = new User();
             u.Name = "Suresh Dasari";
             u.Location = "Hyderabad";
             Console.WriteLine("Name: " + u.Name);
             Console.WriteLine("Location: " + u.Location);
             Console.WriteLine("\nPress Enter Key to Exit..");
             Console.ReadLine();
         }
     }
 }

If you observe the above example, we created properties with get and set accessors without having any logic implementation.

When you execute the above c# program, we will get a result like as shown below.

C# AutoImplemented Properties Example Result

This is how we can create auto-implemented properties in c# applications based on our requirements.

C# Properties Overview

The following are the important points that we need to remember about properties in the c# programming language.