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c# - Get current System.Web.UI.Page from HttpContext?

This is actually a two part question. First,does the HttpContext.Current correspond to the current System.UI.Page object?

And the second question, which is probably related to the first, is why can't I use the following to see if the current page implements an interface:

private IWebBase FindWebBase()
{
    if (HttpContext.Current as IWebBase != null)
    {
        return (IWebBase)HttpContext.Current.;
    }
    throw new NotImplementedException("Crawling for IWebBase not implemented yet");
}

The general context is that some controls need to know whether they are executing as a SharePoint webpart, or as part of an Asp.Net framework.

I have solved the problem by requiring the control to pass a reference to itself, and checking the Page property of the control, but I'm still curious why the above does not work.

The compiler error is: Cannot convert System.Web.HttpContext to ...IWebBase via a reference conversion, boxing conversion, unboxing conversion, wrapping conversion or null type conversion.

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No, from MSDN on HttpContext.Current: "Gets or sets the HttpContext object for the current HTTP request."

In other words it is an HttpContext object, not a Page.

You can get to the Page object via HttpContext using:

Page page = HttpContext.Current.Handler as Page;

if (page != null)
{
     // Use page instance.
}

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