##Reference

1. Programming Windows 8 Apps with HTML, CSS, and JavaScript (Second Preview)
2. http://code.msdn.microsoft.com/windowsapps/
3. http://palermo4.com/post/How-to-Use-IFrames-in-WinRT-Apps.aspx

##Local and Web Contexts within the App Host

1. HTML content in the app package can be loaded into the local or web context
2. The local context has access to the WinRT API, among other things, whereas the web context is allowed to load and execute remote script but cannot access WinRT.
3. Remote content (referred to with http[s]://) always runs in the web context.
4. ms-appx:/// always runs in the local context.
5. ms-appx-web:/// always runs in the web context.
6. The //’s in the WinJS paths refer to shared libraries rather than files in you app package, whereas a single / refers to the root of your package.
7. an app’s home page always runs in the local context, and any page to which you navigate directly (<a href> or document.location) must also be in the local context.
8. Within the local context of an app, ms-appdata is a shortcut to the appdata folder wherein exist local, roaming, and temp folders.ms-appdata can be used only for resources, namely with the src attribute of img, video, and audio elements.

##Use iFrames in WinRT Apps

1. A local context page can contain an iframe in either local or web context

    <iframe src="ms-appx-web:///web.html" width="300" height="400">
    <!-- running in web context -->
    </iframe>
    <iframe src="http://web.html" width="300" height="400">
    <!-- running in web context -->
    </iframe>
    <iframe src="/web.html" width="300" height="400">
    <!-- running in local context -->
    </iframe>
    <iframe src="ms-appx:///web.html" width="300" height="400">
    <!-- running in local context -->
    </iframe>
   	
   	
    <!-- iframe in local context with source in the app package --> 
    <!-- this form is only allowed from inside the local context --> 
    <iframe src=" /frame-local.html"></iframe> 
    <iframe src="ms-appx:///frame-local.html"></iframe> 
   	 
    <!-- iframe in web context with source in the app package --> 
    <iframe src="ms-appx-web:///frame-web.html"></iframe> 
   	 
    <!-- iframe with an external source automatically assigns web context --> 
    <iframe src="http://www.bing.com"></iframe>
   

2. if you use an <a href=”…” target=”…”> tag with target pointing to an iframe, the scheme in href determines the context.

    <h1>iFrame Demo</h1>
    <div>
        <a href="http://palermo4.com" target="framed">Palermo4</a> 
        <a href="http://codefoster.com" target="framed">Codefoster</a>
    </div>
    <iframe name="framed" width="900" height="600">
    </iframe>
   

3. navigating from a web context page to a local context page is not allowed by default, but you can enable this by calling the super-secret function MSApp.addPublicLocalApplicationUri (from code in a local page)

    //This must be called from the local context 
    MSApp.addPublicLocalApplicationUri("ms-appx:///frame-local.html");