Restricting User To Login Multiple Times Using Same Credentials

Generally in many websites after you get logged in you will be redirected to home page. While this page is running if the user selects the new window and open the Login page again and if he provides the same credentials which was provided earlier then he will be automatically redirected to home page.

Here is the explanation of how to restrict this if you consider the examples of gmail.com or yahoo.com once in a particular user is logged in they won’t restrict the user but here It will provide that feature and check whether ifa particular user is logged in It will display it as already logged in.

Concepts:

1)    Basics of handling Cache Memory
2)    Maintaining SQL Session State
3)    Database Retrieval
4)    Maintaining Session ID Uniquely for each user

In my example 2 pages namely

Login.aspx
Home.aspx

Procedure:

a)     Open Visual Studio( use VS2010) and select new project and name it as State Server.
b)    Select a web application from the templates available.
c)     Now name it Default.aspx as Login.aspx
d)    Name About.aspx as Home.aspx.
e)   Follow the steps which explained below.
This procedure can be explained step by step using this way:

Step 1:

Now after adding the pages first we will consider the Login.aspx page in that First and foremost thing is create a class studentInfo of Serializable type to return the values of username and password.

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