true if the current permission is a subset of the specified permission; otherwise, false.
Type Reason ArgumentException target is not null and is not of type System.Security.Permissions.FileIOPermission .
The current permission is a subset of the specified permission if the current permission specifies a set of operations that is contained by the specified permission. For example, a permission that represents read access to C:\example.txt is a subset of a permission that represents read access to C:\. If this method returns true, the current permission represents no more access to the protected resource than does the specified permission.