FileExists Method
Checks if a file with the given Id is present in the cache.
Syntax
Remarks
This method checks to see whether there's a file with the specified FileId present in the cache; returning true if so or false otherwise.
.NET Standard Notes
To call this method in an asynchronous manner call FileExistsAsync instead. When the method completes (or an error is encountered) the FileExistsCompleted event will fire.