When overridden in a derived class, returns the MIME type of the part content.
Assembly: WindowsBase (in WindowsBase.dll)
The derived class does not provide an override implementation required for the method.
is a virtual method of the PackagePart abstract base class. Implement this method only in derived types where the value for the content type cannot be provided at the time of construction, or if calculating the content type value is a nontrivial or costly operation. The return value must be a valid MIME content type.