One of the new global attributes in HTML5 is the hidden attribute. It is not the most advanced or revolutionary attribute in HTML5, since all it does is actually to hide the content of the element.
Last time I wrote about how to use Polymer to create custom elements. This time we will create two custom elements, where one of them is going to use the other to add additional functionality. We will also use CSS Filters and properties unique to this element.
I previously blogged about Shadow DOM where I demonstrated how to use the Developer tools in Google Chrome to get the underlying DOM that is not visible to the user, in this case the video element. This is a great tool to get more understanding about how the element is actually built, and the API makes it possible to create our own Shadow DOM with ”hidden” elements.
In DOM Level 3 Events, a new type of events, CustomEvent, is available. It extends the ordinary Event with a new detail property which you can use to provide extra information. With this new method you are able to create new types of events that you can use in your application.
In the upcoming specification for HTML 5.1, a new semantic element will be introduced, the <main> element.
ASP.NET Web Pages Beta 1 have support for Helpers, which are methods written in C# or Visual Basic, and returns IHtmlString. They can return HTML that is displayed on the page. If you choose to create helpers that way, you would need to have your HTML in an assembly, which makes it different to modify. Because of that, the new version of Razor supports declarative Helpers that you can create directly on the page. They work in both ASP.NET MVC 3 Beta and ASP.NET Web Pages Beta 2, which is included in WebMatrix.
When you install ASP.NET MVC 3 Beta or WebMatrix Beta 2, a new product called ”NuPack” is installed with it. NuPack makes it possible to quickly add references to third party products like Ninject, jQuery and so on. All necessary files (dll, js etc) are automatically added to the project, and necessary modifications in web.config are automatically added.
Microsoft just released ASP.NET MVC 3 Beta, which came with some news. Among other things, we now have a new project dialog box, an updated version of Razor, support for helpers from ASP.NET Web Pages, new interfaces for Dependency Injection, unobtrusive jQuery validation and more. A new beta of WebMatrix has also been released.
New project dialog
When we created new ASP.NET MVC project in CTP's that came before, there were different project types for the Web Forms and Razor syntax. In ASP.NET MVC Beta we have a single project type called ASP.NET MVC 3 Web Application. If we choose to create a new project, we get a new window, where we can choose View Engine, type of ASP.NET MVC 3-projects and if we want a test project:
Updated version of Razor
Unfortunately, we still don´t have syntax highlighting and intellisense for Razor, but for syntax highlighting, you can use either WebMatrix, or this plugin for Visual Studio 2010:
However, there are some new features for Razor in ASP.NET MVC 3, like a new way to specify the model, as well as support for declarative helpers.
Helpers from ASP.NET Web Pages
When ASP.NET Web Pages came with WebMatrix, we got a couple of different helpers like one which is used to show a table, with support for sorting and paging. It can now be used in asp.net MVC 3.
New interfaces for Dependency Injection
ASP.NET MVC 3 CTP came with enhanced support for Dependency Injection, by IMvcServiceLocator. In the new beta, we can use the IDependencyResolver insttead, which is smaller and contains just what we need to inject code in ASP.NET MVC.
There is also a new interface called IControllerActivator, which is used to create an instance of an already existing instance of a controller, i.e. as that the Activator class. Unlike the IControllerFactory it is not used to locate the correct controller.
Unobtrusive jQuery Validation
When we try to post HTML from the client, we will, by default, get an error message that says that potentially dangerous code has been posted. This came in ASP.NET 1.1, and can be turned off in WebForms by setting the ValidateRequest to false.
In ASP.NET MVC, we instead insert a ValidateInput attribute on the controller or action method and set the parameter to false. What´s new in ASP.NET MVC 3 Beta and WebMatrix Beta 2 is that we now can define specific fields you may post HTML, while all others are protected. This provides increased security when we usually do not want to allow HTML in all fields.
A very exciting new feature, and which are included in both ASP.NET MVC 3 Beta and WebMatrix Beta 2 is NuPack. It is a new package manager which makes it possible to download and install modules with just a few clicks. This means that we can get the Ninject, jQuery, ELMAH, and more without having to go to each page and download them manually.
With ASP.NET MVC 3 Beta, we can either use a dialog window in Visual Studio to add packages, or we can use a new command window. With WebMatrix we visit a specific page instead to get access to the modules.
I will mention all the new features in separate blog posts for more in-depth information, but you can already download both ASP.NET MVC 3 and WebMatrix here: