C# Interface Example

In this c# interface tutorial we learn about C# Interface and Abstract Class, difference between interface and abstract class, so you know when to use interface and abstract class in C#.

An interface in C# is the design of any component that only contains the declaration of the methods, properties, and events, interface never contains the implementation part.

C# interface implementation part is done in the class that implements, class:Interface. Interface keep the clean design information, thus makes it easy to maintain a standard information for all.

How to write an Interface in C#?

As you have read that Interface contain only declaration but not implementation, below is an example of interface that contain design declaration about training

interface ITraining
    {
        string Title { get; set; }
        string Subjects { get; set; }
        string Trainer { get; set; }
        string Location { get; set; }
        string TrainingDate { get; set; }
    }

If you see notice in above ITraining interface, there is only declaration about training, but no implementation

Now let’s see how the implementation is done.
Think about some real-time scenario, we can have multiple training going on in any organization, for example .Net Training, here is the implementation.

class DotNetTraining : ITraining
{             
    string _trainer = "WebTrainingRoom";            
    string _title = ".NET Training Room";             
    string _subjects = "Interface, Abstract Class, OOP";             
    string _location = "Online";             
    DateTime _tDate = DateTime.Now;             
                
public string Title            
{             
    get { return _title; }             
    set { _title = value; }             
}
             
                
public string Subjects             
{           
    get { return _subjects; }             
    set { _subjects = value; }             
}
             
                
public string Trainer             
{             
    get { return _trainer; }             
    set { _trainer = value; }             
}
             
                
public DateTime TrainingDate             
{             
    get { return _tDate; }             
    set { _tDate = value; }             
}
             
}

Now similarly we can implement SQL Training, Jquery Training so on, so everywhere training design will remain same.

Look at the picture below, how interface properties have been implemented in different classes.

Hope now have good idea about interface and abstract class in C#, You should also check the difference between Abstract class and Interface.