Skip to main content

What is a Interface in C# .Net

Interface is a type which contains only the signatures of methods, delegates or events, it has no implementation.
Implementation of the methods is done by the class which implements the interface.

Interface is a contract that defines the signature of the functionality. So if a class is implementing an interface it says to the outer world, that it provides specific behavior. Example if a class is implementing ‘Idisposable’ interface that means it has a functionality to release unmanaged resources.

If a class implements an interface then it has to provide implementation to all its methods.

Properties Of Interface:-

  • Supports multiple inheritance(Single Class can implement multiple interfaces).
  • Contains only incomplete method.
  • Can not Contains data members.
  • By Default interface members is public (We Can not set any access modifier into interface members).
  •  Interface can not contain constructors.

Example :- Defining an Interface:

     interface IApp
     {
       int Sum(int i, int j); //By Default Public
     }

     class App : IApp
     {
        public int sum(int i, int j) //Must be declare Public
        {
           return i + j;
        }
    }

Popular posts from this blog

How to validate dropdownlist in JavaScript

In this article you will see how to put validation in dropdownlist by javascript, suppose first item value of dropdownlist is 0 and text is "-Select-" just like given below and we have to validate that at least one item is selected excluding default i.e "-Select-".

Uploading large file in chunks in Asp.net Mvc c# from Javascript ajax

Often we have a requirement to upload files in Asp.net, Mvc c# application but when it comes to uploading larger file, we always think how to do it as uploading large file in one go have many challenges like UI responsiveness, If network fluctuate for a moment in between then uploading task get breaks and user have to upload it again etc.

Customize comment box in blogger

Now it is possible to customize your blogger comment box in simple way there no need to edit HTML of your blogger just through the adding some simple css to the blogger.

How to handle click event of linkbutton inside gridview

Recently I have posted how to sort only current page of gridview , Scrollble gridview with fixed header through javascript , File upload control inside gridview during postback and now i am going to explain how to handle click event of linkbutton or any button type control inside gridview. We can handle click event of any button type control inside gridview by two way first is through event bubbling and second one is directly (in this type of event handling we need to access current girdviewrow container)

Regular expression for alphanumeric with space in asp.net c#

How to validate that string contains only alphanumeric value with some spacial character and with whitespace and how to validate that user can only input alphanumeric with given special character or space in a textbox (like name fields or remarks fields). In remarks fields we don't want that user can enter anything, user can only able to enter alphanumeric with white space and some spacial character like -,. etc if you allow. Some of regular expression given below for validating alphanumeric value only, alphanumeric with whitspace only and alphanumeric with whitespace and some special characters.