Google Launches Nexus 7 Tablet

With the launch of Google's Nexus 7, the $199 tablet market got even more crowded. So, is it the best?

The Kindle Fire, Nexus 7, and Nook Tablet all retail for $199.

Amazon opened a lot of eyes when it introduced the Kindle Fire last year at $199. Many people expected it to come out at $249, but Amazon surprised everybody with $199. Now Google's done the same with its Asus-made Nexus 7, which, on paper anyway, offers the best specs for a 7-inch tablet at its price point, besting its closest competitors, the Kindle Fire and the 8GB Nook Tablet (you could also include the Samsung Tab 2 7.0 in this group, but it starts at $250).

Virtual Keyword In C#

Virtual Keyword in C#

• When a derived class want to override  the base class member(s) then base class member(s)  need to marked as virtual members.


• A function marked as virtual can be overridden by subclasses wishing to provide a specialized implementation.


• Methods, properties, indexers, and events can all be declared as virtual.


• In the derived class those members will be marked by override  keyword.

New Features Of .NET 4.0

Introduction

This article contains some of the new features of ASP.NET 4.0 and Visual Studio 2010 IDE.

Improvements in C# 4.0

C# in .NET Framework 4.0 has some more things to offer. These are:

• Dynamic lookup


• Named


• Optional parameters

Dynamic Lookup

There is a new static type named dynamic. We can use it as object of any type. If there is any error on its usage, we would get it on runtime only. For example:

dynamic integerValue = 1;
dynamic stringValue = " a string";
dynamic Result = integerValue + stringValue;

DataSet Vs DataReader

Dataset Vs DataReader

DataReader

1. DataReader is like a forward only recordset.
2. It fetches one row at a time so very less network cost compare to DataSet(Fethces all the rows at a  time).
3. DataReader is readonly so we can't do any transaction on them.
4. DataReader will be the best choice where we need to show the data to the user which requires no transaction. 
5. As DataReader is forward only so we can't fetch data randomly. .NET Data Providers optimizes the  DataReader to handle huge amount of data.

DataSet

1. DataSet is an in memory representation of a collection of Database objects including tables of a          relational database schemas.
2. DataSet is always a bulky object that requires a lot of memory space compared to DataReader. We can say that the DataSet is a small database because it stores the schema and data in the application memory area.
3. DataSet fetches all data from the datasource at a time to its memory area.
4. We can traverse through the object to get the required data like querying database.

Role-Based Security with Forms Authentication

Introduction

Forms Authentication in ASP.NET can be a powerful feature. With very little code and effort, you can have a simple authentication system that is platform-agnostic. If your needs are more complex, however, and require more efficient controls over assets, you need the flexibility of groups. Windows Authentication gives you this flexibility, but it is not compatible with anything but Internet Explorer since it uses NTLM, Microsoft's proprietary authentication system. Now you must choose how to manage your assets: provide multiple login pages / areas and force users to register for each, or assign groups to users and limit access to pages / areas to particular groups. Obviously, you must choose the latter.