(Windows 8) WinRT demystified

WinRT demystified - Miguel de Icaza

Microsoft has created a cool new UI library called WinRT and they have made it easy to consume from .NET, Javascript and C++ and if you adhere by their guidelines, they will publish the app on their appstore.
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With WinRT, Microsoft has followed a simple rule: if an API is expected to take more than 50 milliseconds to run, the API is asynchronous.
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When you use C# and VB, you are using the full .NET framework. But they have chosen to expose a smaller subset of the API to developers to push the new vision for Windows 8.
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What they did was that they only exposed to the compiler a set of APIs when you target the Metro profile.So your application will not accidentally call File.Create for example. At runtime though, the CLR will load the full class library, the very one that contains File.Create, so internally, the CLR could call something like File.Create, it is just you that will have no access to it.
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