Jack @ ASP.NET

Some members of the C# community were discussing optional parameters and the implications for future versions when optional parameter values change.  In short, you need to realize that changing the value of optional parameters in a public API is a change that is observable at client code. The ramifications vary greatly, from “no big” to “stop the world”. I’ll give a brief explanation of how the feature works, and what you need to watch for and how to separate reasonable caution from irrational fear from using a feature.

While most modern programming languages provide some way of declaring optional function parameters, C# doesn’t provide a way of directly doing so, despite the fact that VB.NET and .NET’s attribute system both support this functionality. This is a subject of some debate currently in the C# community. The C# development team’s position seems to boil down to the following: When provided, this feature is usually nothing more than dressing up method overloading with a little syntactic sugar.

When you get right down to it, their position makes some sense. A function with an optional parameter is in reality two different functions: one that assumes some default behavior if the optional parameter is omitted, and another that performs more specific behavior based on the value of the optional parameter if provided. But that doesn’t change the fact that using overloaded methods to provide optional parameter support feels a little clunky. It works, but you always wind up writing more code, and you pollute your object interface with the extra method signatures required to support all of your optional parameters. Let’s look at some alternatives.

Can BlogEngine.NET be installed within an existing website?

Yes. Install it in its own folder and configure the directory it resides in as an application in IIS.

Some hosting providers may not allow the level of trust used in BlogEngine.NET by default. If you receive an error similar to:

• “Parser Error Message: It is an error to use a section registered as allowDefinition=’MachineToApplication’ beyond application level.”,

You can try one of the following to resolve the issue:

• Comment out the “trust” line in web.config
• Ask your hosting provider if they can configure the directory where BlogEngine.NET is installed as a virtual directory.
• Ask your hosting provider to verify that the directory has been configured as an application in IIS.

How do I update the “About the Author” section of the blog?

In the default Standard theme, edit the content of this section by clicking “edit” in on the side bar of your blog.

An alternative way to display About the Author information is to create a ‘Page’ in the control panel. The Title of the Page can be About the Author. Enter information about the author in the WYSIWYG editor. Once the page has been created, you can add a link to the About page on your blog. This can be achieved by adding a Page List widget, or by adding a TextBox widget with a hyperlink to the About page, or by editing your theme file (site.master) and adding a hyperlink to the About page.

Is BlogEngine.NET open source and completely free?

Yes. BlogEngine.NET is built by passionate developers who have too much spare time, just to make an open source blog engine to give away absolutely free.

Is my mother able to use it?

Yes. We have gone to great lengths to make BlogEngine.NET as easy as possible to use – both from an end user as well as a developer or theme designer’s point of view.

What are the demands for the web server?

The only thing needed to run BlogEngine.NET is a web server that support ASP.NET 2.0 and write permissions on the App_Data folder.

What database is it running on?

None. BlogEngine.NET uses XML to store all posts, pages etc. by default. However, if you prefer to use a database, BlogEngine.NET includes a “DbBlogProvider” that allows you to store data in databases which support standard SQL — MS SQL Server, MySql, SQLite and Vista DB among many others. Configuration changes necessary to store data in a SQL Server database can be found. If there isn’t a data provider already available, you can easily write your own provider. We have enginereed our framework to make this very easy and simple to do.

How can I switch where data is stored (XML to Database or vice versa)?

If you’re just starting off with BlogEngine.NET, all of your data will be stored in XML files in your App_Data folder. Some web hosts such as GoDaddy who have an automatic BlogEngine.NET setup option, might setup your blog so data is stored in a database instead. If your blog is new, you don’t yet have any data, and you want to switch from XML storage to Database storage

Sometimes when you’re having trouble with an ASP.NET site, the problem turns out to not be ASP.NET itself. Here’s the top three issues and their causes. This category are for cases that were concluded because of external reasons and are outside of the control of support to directly affect. The sub categories are 3rd party software, Anti-virus software, Hardware, Virus attacks, DOS attacks, etc.

If you’ve ever run a production website you know there’s always that argument about whether to run anti-virus software in production. It’s not like anyone’s emailing viruses and saving them to production web servers, but you want to be careful. Sometimes IT or security insists on it. However, this means you’ll have software that is not your website software trying to access files at the same time your site is trying to access them.

Here’s the essence as a bulleted list

• Concurrency while under pressure: This causes problems in big software. Make sure your anti-virus software is configure appropriately and that you’re aware of which processes are accessing which files, as well as how, why and when
• Profile your applications: .NET and the Web are not black boxes. You can see what’s happening if you look. Know what bytes are going out the wire. Know who is accessing the disk. Measure twice, cut once, they say? I say measure a dozen times. You’d be surprised how often folks put an app in production and they’ve never once profiled it.
• Anti-Virus Software: It can’t be emphasized enough that site owners should ensure they are running the latest AV engine and definitions from their chosen anti-malware vendor. They’ve see folks hitting hangs due to flakey AV drivers that are over two years out of date.  Another point about AV software is that it is not just about old-school AV scanning of file access. Many products now do low level monitoring of port activity, script activity within processes and memory allocation activity and do not always do these things 100% correctly. Stay up to date!
• Know where you’re calling out to: Also, connection to remote endpoints: calling web services, accessing file systems etc. All of this can slow you down if you’re not paying attention. Is your DNS correct? Did you add your external hosts to a hosts file to remove DNS latency? 
• processModel autoconfig=true: This is in machine.config and folks always mess with it. Don’t assume that you know better than the defaults. Everyone wants to change the defaults, add threads, remove threads, change the way the pool works because they think their textboxes-over-data application is special. Chances are it’s not, and you’d be surprised how often people will spend days on the phone with support and discover that the defaults were fine and they had changed them long ago and forgotten. Know what you’ve changed away from the defaults, and know why.

ASP.NET 4 and Visual Studio 2010 are now available. ASP.NET 4 and Visual Studio 2010 include lots of new features and improvements that enable you to easily build, deploy and manage great Web sites and applications.

Everything You Need to Build Better Websites

Visual Studio 2010

Visual Studio 2010 makes it easier to edit, search, and navigate code. Improved VB and C# Intellisense makes it even easier to find and use classes within the .NET Framework. Improved JavaScript IntelliSense enables better AJAX development. New code navigation and visualization features enable you to quickly find and navigate large projects and visualize dependencies across your code-base. Improved unit testing, debugging and profiling help support building robust applications.

ASP.NET Web Forms
With ASP.NET 4, Web Forms controls now render clean, semantically correct, and CSS friendly HTML markup. Built-in URL routing functionality allows you to expose clean, search engine friendly, URLs and increase the traffic to your Website. ViewState within applications is smaller and can now be more easily controlled. And more controls, including rich charting and data controls, are now built-into ASP.NET 4 and enable you to build applications even faster.

ASP.NET MVC
ASP.NET MVC 2 is now built-into VS 2010 and ASP.NET 4, and provides a great way to build web sites and applications using a model-view-controller based pattern. ASP.NET MVC 2 adds features to easily enable client and server validation logic, provides new strongly-typed HTML and UI-scaffolding helper methods, enables more modular/reusable applications, and facilitates a clean unit testing and TDD workflow with Visual Studio 2010.

Web Deployment
Visual Studio 2010 makes deploying your Websites easy. You can now publish your Websites and applications to a staging or production server from within Visual Studio itself. Visual Studio 2010 makes it easy to transfer all your files, code, configuration, database schema and data in one complete package. VS 2010 also makes it easy to manage separate web.config configuration files settings depending upon whether you are in debug, release, staging or production modes.

The final release of VS 2010 and Visual Web Developer 2010 will have ASP.NET MVC 2 built-in – so you won’t need an additional install in order to use ASP.NET MVC 2 with them.

ASP.NET MVC 2 Features

• New Strongly Typed HTML Helpers
• Enhanced Model Validation support across both server and client
• Auto-Scaffold UI Helpers with Template Customization
• Support for splitting up large applications into “Areas”
• Asynchronous Controllers support that enables long running tasks in parallel
• Support for rendering sub-sections of a page/site using Html.RenderAction
• Lots of new helper functions, utilities, and API enhancements
• Improved Visual Studio tooling support

ASP.NET MVC 2 is the next significant update of ASP.NET MVC. It is a compatible update to ASP.NET MVC 1 – so all the knowledge, skills, code, and extensions you already have with ASP.NET MVC continue to work and apply going forward.

ASP.NET MVC 2 is the next significant update of ASP.NET MVC. It is a compatible update to ASP.NET MVC 1 – so all the knowledge, skills, code, and extensions you already have with ASP.NET MVC continue to work and apply going forward. Like the first release, we are also shipping the source code for ASP.NET MVC 2 under an OSI-compliant open-source license.

ASP.NET MVC 2 is a framework for developing highly testable and maintainable Web applications by leveraging the Model-View-Controller (MVC) pattern. The framework encourages developers to maintain a clear separation of concerns among the responsibilities of the application – the UI logic using the view, user-input handling using the controller, and the domain logic using the model. ASP.NET MVC applications are easily testable using techniques such as test-driven development (TDD).
The installation package includes templates and tools for Visual Studio 2008 SP 1 to increase productivity when writing ASP.NET MVC applications. For example, the Add View dialog box takes advantage of customizable code generation (T4) templates to generate a view based on a model object. The default project template allows the developer to automatically hook up a unit-test project that is associated with the ASP.NET MVC application.
Because the ASP.NET MVC framework is built on ASP.NET 3.5 SP 1, developers can take advantage of existing ASP.NET features like authentication and authorization, profile settings, localization, and so on. Download it at: http://www.microsoft.com/downloads/details.aspx?FamilyID=7aba081a-19b9-44c4-a247-3882c8f749e3&displaylang=en

What is new:

• The new ASP.NET MVC 2 validation feature now performs model-validation instead of input-validation (this means that when you use model binding all model properties are validated instead of just validations on changed values of a model).  This behavior change was based on extensive feedback from the community.

• The new strongly-typed HTML input helpers now support lambda expressions which reference array or collection indexes.  This means you can now write code like Html.EditorFor(m=>m.Orders[i]) and have it correctly output an HTML <input> element whose “name” attribute contains the index (e.g. Orders[0] for the first element), and whose “value” contains the appropriate value.

• The new templated Html.EditorFor() and Html.DisplayFor() helper methods now auto-scaffold simple properties (and do not render complex sub-properties by default).  This makes it easier to generate automatic scaffolded forms.  I’ll be covering this support in a future blog post.

• The “id” attribute of client-script validation message elements is now cleaner.  With RC1 they had a form0_ prefix.  Now the id value is simply the input form element name postfixed with a validationMessage string (e.g. unitPrice_validationMessage).

• The Html.ValidationSummary() helper method now takes an optional boolean parameter which enables you to control whether only model-level validation messages are rendered by it, or whether property level validation messages are rendered as well.  This provides you with more UI customization options for how validation messages are displayed within your UI.

• The AccountController class created with the default ASP.NET MVC Web Application project template is cleaner.

• Visual Studio now includes scaffolding support for Delete action methods within Controllers, as well as Delete views (I always found it odd that the default T4 templates didn’t support this before).

• jQuery 1.4.1 is now included by default with new ASP.NET MVC 2 projects, along with a –vsdoc file that provides Visual Studio documentation intellisense for it.

• The RC2 release has some significant performance tuning improvements (for example: the lambda based strongly-typed HTML helpers are now much faster).