Cookies

What is Cookie?

When user visits a website for the first time a .txt file is sent to user's web browser and stored in a user system in a particular location, This text file is termed as cookie.

Use of cookie?

The main purpose of cookies is to know the user who visited websites.  For instance, you can also save a small piece of information inside cookies.

You might have seen almost every website login page having one checkbox "Remember Me on this computer". These websites store the login information like  username and password inside the cookies. So, next time when user logs  in, the  website retrieves  the information from cookies and you will be logged in automatically.

Types of cookies:

1) Session Cookies: This cookie is stored temporary in the client machine. That means, when user closes the browser this session will be deleted from the client machine. This cookie is also called transient cookies.

2)Persistent Cookies: Persistent cookies is stored on the client hard drive in a particular location until it is not expired. That means persistent cookies  hold the information until its expiry date and time.

Lets see how to work with cookies.

Like every Server side programming language ASP.NET also have Cookies class to deal with cookies.

To assign the value into cookies

HttpCookie myCookie = new HttpCookie("myCookie"); //Create the instance of HttpCookie class
myCookie.Values.Add("username", "MyUserName"); // Add Key and its value to Cookies
myCookie.Values.Add("password", "MyPassword"); // add Another key and value.

We have stored the value into cookies now we will see how to retirve value from cookies

To retrive the value from Cookies

HttpCookie cookie = Request.Cookies.Get("myCookie");
string UserName = cookie.Values["username"];
string Password = cookie.Values["password"];

NOTE : You should not store any critical information into cookies, as its visible and stored into client machine.