An Existing MVC application in Visual Basic .NET

Generation QR Code 2d barcode in Visual Basic .NET An Existing MVC application

An Existing MVC application
Drawing QR-Code In VB.NET
Using Barcode printer for VS .NET Control to generate, create QR Code JIS X 0510 image in .NET applications.
www.OnBarcode.com
QR Code Recognizer In VB.NET
Using Barcode recognizer for VS .NET Control to read, scan read, scan image in VS .NET applications.
www.OnBarcode.com
I think it is useful to start by looking at what a popular application built using MVC looks like. You might be familiar with the Stack Overflow (SO) site. SO is a popular programming web site in which users can ask programming questions to be answered by other users. Other users then answer the questions. These answers are then voted on by other users; those with the most votes (hopefully the best ones!) move to the top of the answer list. Let s take a look at SO now: 1. 2. 3. Open up a browser and go to http://www.stackoverflow.com. Take a look around the site, paying particular attention to the URL of each page. Imagine that you were creating an application similar to SO but were writing it using web forms. How might you construct it
Draw QR Code 2d Barcode In Visual Basic .NET
Using Barcode drawer for Visual Studio .NET Control to generate, create Denso QR Bar Code image in .NET applications.
www.OnBarcode.com
DataMatrix Generation In Visual Basic .NET
Using Barcode creator for .NET Control to generate, create ECC200 image in VS .NET applications.
www.OnBarcode.com
At a very simple level in a traditional ASP.NET application, you would probably have two pages: one to list all the questions users have asked and another page to display the actual question and answers. From the question list page, you would then pass a question ID in the query string through to the detail page and retrieve the relevant answers. For example when a user clicks on a question the URL might look something like http://www.stackoverflow.com/questionDetail.aspx id=3434. Now click any question in SO and take a look at the URL. You will see something similar to http://stackoverflow.com/questions/294017/visual-studio-2005-freezes.
Paint GS1-128 In VB.NET
Using Barcode encoder for Visual Studio .NET Control to generate, create USS-128 image in .NET applications.
www.OnBarcode.com
PDF417 Creation In VB.NET
Using Barcode creation for .NET Control to generate, create PDF417 image in .NET framework applications.
www.OnBarcode.com
ASP.NET MVC
Encode Linear 1D Barcode In Visual Basic .NET
Using Barcode drawer for Visual Studio .NET Control to generate, create Linear 1D Barcode image in VS .NET applications.
www.OnBarcode.com
Create UPC-E In VB.NET
Using Barcode creation for VS .NET Control to generate, create UPC - E0 image in Visual Studio .NET applications.
www.OnBarcode.com
This URL is superior to the query string version for a number of reasons:
QR Code ISO/IEC18004 Printer In Java
Using Barcode printer for Java Control to generate, create QR Code JIS X 0510 image in Java applications.
www.OnBarcode.com
Decoding QR In None
Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications.
www.OnBarcode.com
Search engines index it better than a query string version. At the time of writing, Google seems to give a higher precedence to pages with the search term in the URL. It s more readable to humans. If you had a product site it s a lot easier for users to remember an address like http://www.microsoft.com/vs2010/ than http://www.microsoft.com/product/productDetail.aspx id=4563432234. The URL can assist other developers integrating with your application to understand how it works. For example, if you examine the question detail page (as shown in Figure 13-1), you will see the answer posts to /questions/740316/answer. You can probably figure out that 740316 is an ID for the question, and it wouldn t be too tricky to develop an addition to post answers.
Code-39 Creator In C#
Using Barcode maker for VS .NET Control to generate, create Code 39 Extended image in Visual Studio .NET applications.
www.OnBarcode.com
Make Barcode In None
Using Barcode encoder for Office Word Control to generate, create Barcode image in Office Word applications.
www.OnBarcode.com
Figure 13-1. Stack Overflow web site
Painting Code 39 Extended In Java
Using Barcode generator for Java Control to generate, create USS Code 39 image in Java applications.
www.OnBarcode.com
QR-Code Generator In Java
Using Barcode generation for Java Control to generate, create QR image in Java applications.
www.OnBarcode.com
an example of an ASP.NET MVC application
Printing ECC200 In .NET
Using Barcode encoder for ASP.NET Control to generate, create Data Matrix ECC200 image in ASP.NET applications.
www.OnBarcode.com
QR Code 2d Barcode Generator In None
Using Barcode creator for Online Control to generate, create QR-Code image in Online applications.
www.OnBarcode.com
This facility is called routing and although it isn t specific to ASP.NET MVC, it is an important concept.
ANSI/AIM Code 128 Maker In None
Using Barcode generation for Software Control to generate, create Code 128 Code Set C image in Software applications.
www.OnBarcode.com
Print EAN 13 In None
Using Barcode printer for Word Control to generate, create EAN13 image in Microsoft Word applications.
www.OnBarcode.com
TIP Routing is available in ASP.NET 4.0 and net 3.5sp1 (see 10 for more details), so don t think you have to use ASP.NET MVC to take advantage of this.
Barcode Creation In C#
Using Barcode printer for .NET framework Control to generate, create Barcode image in .NET applications.
www.OnBarcode.com
Making QR Code In None
Using Barcode maker for Microsoft Word Control to generate, create QR Code 2d barcode image in Word applications.
www.OnBarcode.com
ASP.NET MVC
ASP.NET MVC uses the requested URL to decide how to route users requests to a special class called a controller that in turn interacts with your applications model. Before you get started with creating a simple application, you should also be aware of the following:
MVC has no Viewstate. Type initialization syntax.
What a State
ASP.NET MVC does not use viewstate. Viewstate is used in ASP.NET WebForm applications to maintain the state of controls such as the item that is selected in a drop-down menu between page posts. By default in ASP.NET, all controls have viewstate, which can bloat pages and slow an application down. Viewstate is often unnecessary; by removing it you can reduce page size and increase the speed of the application because the web server no longer has to parse it and load control state. Partly due to the lack of viewstate (and because it is kind of missing the point of ASP.NET MVC), you probably should not be using standard ASP.NET controls such as <asp:hyperlink /> in your MVC application. That s not to say these controls and tags will not work (although many such as DataGrid might give you issues), but it is not keeping with the clean ASP.NET MVC way of doing things, so don t do it! As you will see later in the chapter, ASP.NET MVC offers many ways of writing HTML. As you can imagine, the lack of view state can be problematic after all, ASP.NET s developers did not add it without reason! Imagine, for example, creating a new data paging, orderable data grid control without viewstate and you can see that ASP.NET MVC also has the potential to complicate your life!
Copyright © OnBarcode.com . All rights reserved.