The PIAnnotations IsFile parameter is true if the Value of the annotation is a file. It is returned as a read-only Boolean.
The object placeholder is an object expression that evaluates to a PIAnnotation object.
This is a read only property. It is set when you Import a file to the annotation.
You can use this property to determine whether or not an annotation's Value is a file. If it is, you can use the Export method to restore the file.