What is Visual Studio LightSwitch ?
Visual Studio LightSwitch is a new rapid application development tool from Microsoft for building business applications with less emphasis on coding. It helps to simplify development process, coz it lets you to concentrate on the business logic and does a lot of remaining work for you. LightSwitch applications can be desktop based giving them the ability to interact with hardware devices such as card readers, scanners etc or browser based applications which helps to attain a greater reach. Since LightSwitch applications are created using Silverlight and .Net based n-tier architecture, there will be little change in the look and feel and behavior of both desktop based ones and web based ones.
Visual Studio LightSwitch offers a wide range of pre-built templates and tools to build business application that target Windows Client and Windows Azure. It also helps domain experts to build applications by concentrating on developing business logic, with little focus on writing code. Every business application will have common features such as searching, sorting, rearranging grids, ability to export data etc. With applications developed using LightSwitch these kind of features are already built in. Common data operations such as adding, updating, saving, deleting are also built in and it provides basic validation logic.
Architecture Overview
Most of the business applications are based on n-tier framework and among them the 3-tier architecture is widely used. Typical 3-tier architecture will look like as given below.
The presentation layer is the top most level of the framework, interacts with the end users, ie where the information is captured. It acts as a bridge between the application and the end users. The Business Layer coordinates the application, processes commands, making logical decisions and evaluations, and performs calculations. It also moves and processes data between the two surrounding layers. The Data Layer manages the storage and retrieval of information from data sources such as database or a file system . The information is then passed to the logic tier for processing, and then eventually back to the user. Designing and developing a new 3-tier architecture from scratch is tedious and time consuming. Many factors such as communication between the layers, technology to be used, system design, security etc needs to be factored in. But LightSwitch frees developer from making these decisions by making specific technology choices for you.
In a whole , presentation layer in a LightSwitch application can be a Silverlight 4.0 application, which can run as windows as well as a web application. The data layer can be thought as a set of WCF RIA Domain services running in ASP.NET 4.0 and can be hosted locally or on an IIS Server or in a Windows Azure Web Role. The data layer uses SQL Server or SQL Azure as primary data storage and can consume data from existing SharePoint 2010 lists, databases accessible via EDM provider and custom build WCF RIA Domain Services.
