This function causes the viewer to close the current image, reverting the viewer back to a state where it is not displaying an image. Unlike the openPage function, this function does not need to interact with the server, so it will complete it's operation (including raising the pageClosed event) before it returns. Like most other viewer operations, the visual appearance of the viewer will not be updated immediately; instead the viewer will wait until the browser is idle before updating its appearance.

If you call this function while an openPage operation is pending, the control will cancel the pending operation and it will not raise the cancelled pageOpened event.

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